laravel route {id} get from controller code example

Example 1: laravel 8 routes namespace

Route::group(['namespace' => 'App\Http\Controllers', 'prefix' => 'admin',
 'as' => 'admin.', 'middleware' => ['auth:sanctum', 'verified']], function()
{
    Route::get('/dashboard', ['DashboardController', 'index']);
});

Example 2: laravel route optional parameter

Route::get('/sample/{param?}', 'SampleController@index');