If you want to let a family member use some of your favorite apps, media content, and iCloud storage, use Apple Family Sharing. It lets you share stuff with up to five family members, from music to TV+ movies. This is also useful for letting family members use your device without letting them know your individual Apple ID. As an adult (the organizer), just invite the others to join, then select which services can be shared. The other members still see their own personal content and recommendations personalized for their Apple IDs.