How to redirect to 404 page if page don't exist

1

I created error page, I have error.html.twig file. My address is
http://localhost/GRAV/ when I type http://localhost/GRAV/loremipsum I should see 404 page but instead I see my home page which have broken css. How Can I redirect to 404?

@edit, nevermind, working now :smiley: