Watching Apple TV app
Can you watch Apple TV through a Roku? (If you subscribe to Apple TV)
Can you watch Apple TV through a Roku? (If you subscribe to Apple TV)
Select Roku devices can install the Apple TV app.
Then you can watch Apple TV+ in the Apple TV app on your Roku, when signed in with an Apple ID account (that has that subscription).
Devices you can use with the Apple TV app and Apple TV+ - Apple Support
Watching Apple TV app