validation

How can I just verify my rules on a submit? I followed the User Guide. But it is not clear enough for me. Since I set my Rules even on the first load I get all the errors which makes sense. How can I avoid it in the CI4 way?

Here is the controller:

       

PHP Code:

helper(['form', 'url']);
$validation =  \Config\Services::validation();
    
        
        $validation->setRules([
            'username' => ['label' => 'username', 'rules' => 'required|min_length[5]'],
            'password' => ['label' => 'password', 'rules' => 'required|min_length[5]']
        ]);

      
        
        if ($validation->withRequest($this->request)->run()) {
            // Input was OK
        } 

        echo view('Login', ['validation' => $validation]); 


In my view I have:

Code:

<div><?php echo $validation->listErrors(); ?></div>