Create a photo screen saver on Apple TV
You can use shared photos or albums in the Photos app as your Apple TV screen saver.
Set a screen saver
Open the Photos app on Apple TV, then swipe to the Shared category in the menu bar.
Note: If you can’t see the Shared category, go to Settings >Accounts > iCloud and turn on Shared Albums.
Select an album, then select Set as Screen saver and confirm.
Adjust screen saver settings
Open Settings on Apple TV.
Go to General > Screen Saver.