My son no longer owns an Apple device, I removed him from family sharing. How do I share Apple TV or Music with him?

It depends upon the devices he now has, but you should not have removed him from Family Sharing. You will have to invite him again. To learn how to join a Family Sharing group, read the section "Join a family group" in the document "Set up Family Sharing". This link will take you straight there --> Set up Family Sharing - Apple Support

Use Apple Music with your Android devices - Apple Support

Click on this link to see 'All the ways to watch Apple TV+' --> How to watch Apple TV+, MLS Season Pass, and more - Apple Support

Family Sharing is not limited to Apple devices. You can use Family Sharing to share Apple TV and Music and your son can access the shared subscriptions on Android and Windows devices, game consoles, smart TVs and streaming devices that support the Apple TV and Music apps.

Invite him to Family sharing again, so he can access the shared subscriptions. Then he can log in with his Apple ID on whatever other devices he has and use the subscriptions in the relevant apps for those devices.