Error 404 Object not found

Thank you for the hints.

Now I understand the constructs of an URL:
http://example.com/[controller-class]/[controller-method]/[arguments]

So, I know my page1.php should be a method of the controller-class login.php.

But I still don´t know how it helps me to open the view second_message.php if I click on the login-button.

So when I change to a method in the controller-class, what do I write in: .....action= ''.....