How to see if another device has my Apple ID

See -> Check your Apple ID device list to see where you're signed in

Check your Apple ID device list to find where you're signed in - Apple Support

• if you see devices that don't belong to you, delete from your account.

See also -> If you think your Apple ID has been compromised

If you think your Apple ID has been compromised - Apple Support

For starters:

See who has access to your iPhone or iPad - Apple Support

Then:

Check your Apple ID device list to find where you're signed in - Apple Support

Also: if you have iCloud+, you can check any private relay logins at the App level under

Icloud>Sign-in & Security>Sign in with Apple

This will show you apps using private logins behind the scene that you approved at some point.