Chrome does not let you customize the new tab page. The new tab page always opens a custom Google Search page, and Chrome extensions do not work on this page.
This extension lets you point the new tab page to a URL of your choice. It can be Google.com, your company's homepage, or a blank page.
It is lightweight on your browser (<50kb - compared to, for example, Grammarly, which is 36MB), has no tracking, and is straightforward to use.