Apple ID, creation and transfer of account

Hey! Thanks for reaching out.

To create an Apple ID, follow the link below to learn how.

Create and start using an Apple ID - Apple Support

To log with the new Apple ID on the device, follow the link below for more information!

Sign in with your Apple ID - Apple Support

Unfortunately, sharing an AppleID was a bad strategy - you can't "transfer" your stuff

BUT

After setting up your own (see 200CAD's links), y'all can set up Family Sharing to share content you purchased.

see Winston Churchill's response in the below discussion

How to transfer all files from one iCloud account to another

Family Sharing - Use your own Apple ID for Family Sharing

Family Sharing -What types of content can I share?

Family Sharing - If you don‘t see your family‘s shared content

Family Sharing - Ask to Buy

Family Sharing - purchases and payments

Family Sharing - Hide and unhide music, movies, TV shows, audiobooks, and books

Family Sharing – share iCloud Storage

Family Sharing - Share an iCloud storage plan with your family

Family Sharing and location