I am new in laravel 8 & I am trying to edit & show the value of that perticular fild in a form and i am able to show it in that field.
But when i am trying to add another data it is showing Undefined variable: UserRegistration.
If anyone kindly help..

My registration.blade.php code:-

<form action="{{$url}}", method="POST">

                                        @csrf

                                    <div class="row">
                                        <div class="col-md-6 mb-4">
                                            <div class="form-outline">
                                                <input type="text" id="form3Example1m" name="Fname"
                                                    class="form-control form-control-lg" value="{{$UserRegistration->Fname}}" />
                                                <label class="form-label" for="form3Example1m">First name</label>
                                            </div>
                                        </div>
                                        <div class="col-md-6 mb-4">
                                            <div class="form-outline">
                                                <input type="text" id="form3Example1n" name="Lname"
                                                    class="form-control form-control-lg" value="{{$UserRegistration->Lname}}" />
                                                <label class="form-label" for="form3Example1n">Last name</label>
                                            </div>
                                        </div>
                                    </div>

                                    <div class="row">
                                        <div class="col-md-6 mb-4">
                                            <div class="form-outline">
                                                <input type="text" id="form3Example1m1" name="mother"
                                                    class="form-control form-control-lg" value="{{ $UserRegistration->mother}}" />
                                                <label class="form-label" for="form3Example1m1">Mother's
                                                    name</label>
                                            </div>
                                        </div>
                                        <div class="col-md-6 mb-4">
                                            <div class="form-outline">
                                                <input type="text" id="form3Example1n1" name="father"
                                                    class="form-control form-control-lg" value="{{$UserRegistration->father}}" />
                                                <label class="form-label" for="form3Example1n1">Father's
                                                    name</label>
                                            </div>
                                        </div>
                                    </div>

                                    <div class="form-outline mb-4">
                                        <input type="text" id="form3Example8" name="address" value="{{$UserRegistration->address}}" class="form-control form-control-lg" />
                                        <label class="form-label" for="form3Example8">Address</label>
                                    </div>

                                    <div class="d-md-flex justify-content-start align-items-center mb-4 py-2">

                                        <h6 class="mb-0 me-4">Gender: &nbsp;</h6>

                                        <div class="form-check form-check-inline mb-0 me-4">
                                            <input class="form-check-input" type="radio" name="gender"
                                                id="femaleGender" value="M"{{$UserRegistration->gender=='M'?'checked':''}} />
                                            <label class="form-check-label" for="femaleGender">Male</label>
                                        </div>

                                        <div class="form-check form-check-inline mb-0 me-4">
                                            <input class="form-check-input" type="radio" name="gender"
                                                id="maleGender" value="F" {{$UserRegistration->gender=='F'?'checked':''}} />
                                            <label class="form-check-label" for="maleGender">Female</label>
                                        </div>

                                        <div class="form-check form-check-inline mb-0">
                                            <input class="form-check-input" type="radio" name="gender"
                                                id="otherGender" value="O" {{$UserRegistration->gender=='O'?'checked':''}} />
                                            <label class="form-check-label" for="otherGender">Other</label>
                                        </div>

                                    </div>

                                    <div class="row">
                                        <h6 class="mb-0 me-4">State: &nbsp;</h6>

                                        <div class="col-md-6 mb-4">

                                            <select class="select" name="state">
                                                <option value="">State</option>
                                                <option value="Khulna" {{$UserRegistration->state=='Khulna' ? 'selected':''}}>Khulna</option>
                                                <option value="Dhaka" {{$UserRegistration->state=='Dhaka' ? 'selected':''}}>Dhaka</option>
                                                <option value="Dinajpur" {{$UserRegistration->state=='Dinajpur' ? 'selected':''}}>Dinajpur</option>
                                            </select>

                                        </div>
                                    </div>

                                    <div class="row">
                                        <h6 class="mb-0 me-4">City: &nbsp; &nbsp;</h6>
                                        <div class="col-md-6 mb-4">
                                            {{-- <h6 class="mb-0 me-4">City: &nbsp;</h6> --}}
                                            <select class="select" name="city">
                                                <option value="">City</option>
                                                <option value="Khulna" {{$UserRegistration->state=='Khulna' ? 'selected':''}}>Khulna</option>
                                                <option value="Dhaka" {{$UserRegistration->state=='Dhaka' ? 'selected':''}}>Dhaka</option>
                                                <option value="Dinajpur" {{$UserRegistration->state=='Dinajpur' ? 'selected':''}}>Dinajpur</option>
                                            </select>

                                        </div>
                                    </div>

                                    <div class="d-flex justify-content-end pt-3">
                                        <button type="button" class="btn btn-light btn-lg mr-3">Reset all</button>
                                        <button type="submit" name="submit" class="btn btn-warning btn-lg ms-2">{{$btntitle}}</button>
                                    </div>

                        </form>

My controller UserSignup.php file:-

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Models\UserRegistration;

class UserSignup extends Controller
{
    //
    public function homePage(){

        return view('home');
    }
    
    public function signup(){

        $url=url('/usersignup');
        $title="Student registration form";
        $btntitle="Submit";
        
        $data=compact('url','title','btntitle');
        
        return view('registration')->with($data);
    }

    public function storeData(Request $request){
        
        //insert into table

        $UserRegistration=new UserRegistration;
        
        $UserRegistration->Fname=$request['Fname'];
        $UserRegistration->Lname=$request['Lname'];
        $UserRegistration->mother=$request['mother'];
        $UserRegistration->father=$request['father'];
        $UserRegistration->address=$request['address'];
        $UserRegistration->gender=$request['gender'];
        $UserRegistration->state=$request['state'];
        $UserRegistration->pincode=$request['pincode'];
        $UserRegistration->course=$request['course'];
        $UserRegistration->city=$request['city'];
        $UserRegistration->email=$request['email'];
        $UserRegistration->dob=$request['dob'];

        $UserRegistration->save();

        return redirect('/signup/view');
    }


    public function viewData(){
        
        // show data
        $UserRegistration=UserRegistration::all();

        $data=compact('UserRegistration');
        return view("customer-view")->with($data);

    }

    

    public function edit($id){

        $UserRegistration=UserRegistration::find($id);

        if (is_null($UserRegistration)) {
            # not found
            return redirect('/signup/view');
        }else{

            $url=url('/signup/update')."https://stackoverflow.com/".$id;

            $title="Update Student registration form";
            $btntitle="Update";
            $data=compact('UserRegistration','url','title','btntitle');
            return view('registration')->with($data);
        }

        
    }

    public function update($id,Request $request)
    {
        $UserRegistration=UserRegistration::find($id);

        $UserRegistration->Fname=$request['Fname'];
        $UserRegistration->Lname=$request['Lname'];
        $UserRegistration->mother=$request['mother'];
        $UserRegistration->father=$request['father'];
        $UserRegistration->address=$request['address'];
        $UserRegistration->gender=$request['gender'];
        $UserRegistration->state=$request['state'];
        $UserRegistration->pincode=$request['pincode'];
        $UserRegistration->course=$request['course'];
        $UserRegistration->city=$request['city'];
        $UserRegistration->email=$request['email'];
        $UserRegistration->dob=$request['dob'];

        $UserRegistration->save();
        return redirect('/signup/view');

    }
}

web.php :-

Route::get('/home',[UserSignup::class,'homePage']);

Route::get('/signup',[UserSignup::class,'signup']);
Route::post('/usersignup',[UserSignup::class,'storeData']);

Route::get('/signup/view',[UserSignup::class,'viewData']);

Route::get('/signup/delete/{id}',[UserSignup::class,'delete'])->name('customer.delete');

Route::get('/signup/edit/{id}',[UserSignup::class,'edit'])->name('customer.edit');
Route::post('/signup/update/{id}',[UserSignup::class,'update'])->name('customer.update');