With cPanel you can easily customize the error pages for your website.
Custom error pages are used to give the user more detailed information when the requested page has an error. The most commonly used customer error page is a 404 error page. A 404 error occurs when the requested page does not exist. It may be necessary to create the error page, depending on how you would like to handle the error.
To create custom error pages:
Go to control panel main page
Click on the error page code that you’d like to create