how do I change my tv provider from directv to dish

The TV provider setting can be found in Settings﹥Users and Accounts﹥[ᴀᴘᴘʟᴇ ᴛᴠ ᴀᴄᴄᴏᴜɴᴛs] TV Provider﹥.

Set up single sign-on with your TV provider on Apple TV - Apple Support

TV providers that let you sign in on your iPhone, iPad, or Apple TV - Apple Support

Apple TV 4K, tvOS 11

If that is still accurate, then please consider updating your system software to the current version (tvOS 14.5). How to update your Apple TV - Apple Support