from where laravel route fetch value code example

Example 1: named route with parameter laravel

Route::get('/menu/{category}/{product}/{item}', ['as' => 'named.route' , 'uses' => 'MenuController@listItem']);

// to get the actual linke
route('named.route', ['category' => $category->id, 'product' => $product->id, 'item' => $item->id]);

Example 2: laravel route pattern

Route::pattern('id', '[0-9]+');
Route::get('user/{id}', function ($id) {
    // Only executed if {id} is numeric...
});