Answers for "Illuminate\Contracts\Container\BindingResolutionException Target class [App\Project] does not exist."

IlluminateContractsContainerBindingResolutionExceptionTarget class [ProjectController] does not exist.

# ajouter le controller
use AppHttpControllersProjectController;


Route::resource('/projects', ProjectController::class);

IlluminateContractsContainerBindingResolutionException target calss does not exist

Routing namespaces have been updated on Laravel 8.X

On your router, you should define:
use AppHttpControllersTestController;

And then, declare:
Route::get('test',[TestController::class, 'test']);