Target class [CustomersController] does not exist. in laravel 8 code example

Example 1: target class admin homecontroller does not exist laravel 8

Route::get('/home', 'App\Http\Controllers\HomeController@index')->name('home');

Example 2: Target class [SallyController] does not exist.

//In laravel 8 uncomment  protected $namespace='App\\Http\\Controllers';