HOW TO CHANGE INTERNET PROVIDERS FOR MY APPLE TV

You need to choose and set up an account with a provider.

Use your pay TV or cable provider with Apple TV - Apple Support

Apple TV doesn’t care who your ISP is, no change needed. That is for your router settings, not for the network connected devices. If you have TV channels bundled with internet connectivity, then the TV part could influence Apple TV as well, as babowa pointed out.