Stop family sharing
how do I know if I have more than one Apple ID on my iphone
iPhone 14, iOS 16
Question marked as
See the article 'Leave [/Cancel] Family Sharing', click here--> Leave Family Sharing - Apple Support
Shortcut to: Disband a family group --> Leave Family Sharing - Apple Support
In general it helps not to have too many unrelated questions going in one topic.
In general only a single ID can be signed in on a phone at any one time. There are a few places where you can have a second one, namely in Messages, in the iTunes and App Store, and as an extra address in Mail.