I have two phones w/ same Apple ID. How do I change the Apple ID on one phone?

I have two phones w/ same Apple ID. Trying to use location sharing and one phone won't locate the other phone. I figure each phone needs it's own Apple ID. I've tried everything and I don't want to mess anything up. I even created a second Apple ID but can't activate it because the other Apple ID uses that email address for authentication or something. How do I change the Apple ID on one phone with out messing up the other phone?

I'm trying to change the Apple ID on LB iPhone 11

The other phone is LeeAnn Work iphone SE

Thanks!!!