You can simply redirect 404 page in Laravel by redirecting in the Route.
All you need to do create 404 template page and redirect via Route.
404.blade.php
<!doctype html>
<html lang="{{ app()->getLocale() }}">
<head>
<metacharset="utf-8">
<metahttp-equiv="X-UA-Compatible"content="IE=edge">
<metaname="viewport"content="width=device-width, initial-scale=1">
<title> 404 - Page not found</title>
</head>
<body>
The page your looking for is not found
</body>
</html>
Route.php
Route::any(‘{slug’},function(){
Return view(‘404’);
});
