It is always a better practice to create your own code for authentication/ registration as you will need to make some alterations in flow of authentication which will get over-written when you update/upgrade laravel application. I Prefer to create controllers inside Auth to handle my Login and Registration. I am pasting a code snippet for Login along with routes for better understanding.

Route::get('login', 'Auth\[email protected]');

Route::post('login', 'Auth\[email protected]');

Route::get('logout', 'Auth\[email protected]');

    
 <?php

    namespace App\Http\Controllers\Auth;

    use App\Http\Controllers\Controller;
    use Illuminate\Foundation\Auth\AuthenticatesUsers;
    use Illuminate\Http\Request;
    use Illuminate\Support\Facades\Auth;

    class LoginController extends Controller
    {
        /*
        |--------------------------------------------------------------------------
        | Login Controller
        |--------------------------------------------------------------------------
        |
        | This controller handles authenticating users for the application and
        | redirecting them to your home screen. The controller uses a trait
        | to conveniently provide its functionality to your applications.
        |
        */

        use AuthenticatesUsers;

        /**
         * Where to redirect users after login.
         *
         * @var string
         */
        protected $redirectTo = '/home';

        /**
         * Create a new controller instance.
         *
         * @return void
         */
        public function __construct()
        {
          $this->middleware('guest')->except('logout');
        }

        public function showLoginForm()
        {
          return view('auth.login');
        }
        public function login(Request $request)
        {
          if (Auth::attempt(
           ['email' => $request['email'],
           'password' => $request['password'],
           ], 1)) {
            return redirect('home');
               
        } else {
          return redirect('login')->with('message', 'Login Failed');
        }
      }

      public function logout(Request $request)
      {
        $this->guard()->logout();

        $request->session()->flush();

        $request->session()->regenerate();

        return redirect('/login');
      }
    }

Thanks for the answer,

i have an auth controller as you describe my problem is, that Auth::attempt checks the same database table for the username/email and password, but i need the username and the password in two seperated tables.

In that case try doing it with DB OR Models by joining two tables where you have stored username and password stored. Check if that combination exist. I am considering that you have a user table where users are stored and a password table which has username/id as foreign key from user table. A sample query may look like.

$user=DB::table('users')::join('password','password.username','users.username')
->where('username',$request->input('username'))
->where('password',$request->input('password'))
->first();

if user object is empty then user is not autheniticated other you can log in the user using login function of Auth class. Auth::login($user);

Okay thank you, i will give this a try.