404 Error Page: If a website visitor types in the wrong URL for a specific page, most websites have a 404 error page to let them know that the URL they used did not work or the URL they entered does not exist.
If you want your website visitors to go to a customized 404 error page, you can create a new page in your website and label the “address” for that page to be “404”.
If your website visitor types the wrong URL for a specific page or you have a link to a page that is broken, it will send them to your customized 404 error page.
Page Settings for the customized 404 error page
