Changing your Apple ID
If I change my Apple ID on my iPhone will I lose all my information if I create a new one.
Question marked as
Top-ranking reply
If you create/use a new Apple ID, you will lose access to some of your data and the purchases made with your existing Apple ID. Try doing a name change instead. You will be able to access your data and prior purchases.
Note the restrictions in the article.
What to do after you change your Apple ID or password - Apple Support I suggest doing this before you change your Apple ID or password.