apple tv 3rd generation

you connect the optical port to an optical port in the reciever

https://www.maketecheasier.com/assets/uploads/2019/04/apple-tv-differences-hero.jpg

Apple TV →[HMDI]→ AV receiver →[HMDI ARC]→ TV

or

Apple TV →[HMDI]→ TV →[HMDI ARC]→ receiver

or

Apple TV →[HMDI]→ TV →[optical]→ receiver

or

Apple TV →[HMDI]→ TV

↘︎[optical]→ receiver