I don't have apple products

An Apple TV is an Apple product. You watch movies on Apple TV by buying one.

Buy Apple TV 4K - Apple

If you are referring to the Apple TV app, then there are other devices that support it including Samsung TVs, Roku, and Amazon Fire Stick.

See here: Apple TV app - Devices - Apple

What is the exact text of the error message?

If its saying your Apple ID has not yet been used with the iTunes store, you’ll need to sign in to iTunes. You can do so on a Windows PC, and generate the iTunes Store account. You just need to sign in. there’s nothing else that should need to be done.

https://www.apple.com/itunes/download/

Set up and manage an iTunes Store account on PC - Apple Support