Unless you intend to create issues with unintentional sharing of data, you don’t.
As for your immediate problem, are you sharing an AppleID? If so, this is the root of the problem. The first and golden rule - don’t share an AppleID; both you and your daughter require a separate AppleID to maintain separation and control of data.
You should set-up Family Sharing, creating an AppleID account for you daughter in the process - ensuring that her age is correctly configured during the account setup.
More information about Family Sharing and its setup:
Set up Family Sharing – Apple Support
Family Sharing – Apple Support
Share App Store, iTunes Store and Apple Books purchases with Family Sharing – Apple Support