Hi Apple_family_sharing,
Thank you for using the Apple Support Communities! To share iCloud+ with your family, please follow the steps below that can help:
Share iCloud+ with your family
In iOS 16 or iPadOS 16 or later:
1. If you haven't set up Family Sharing yet, set up Family Sharing.
2. Go to Settings > Family.
3. Tap Subscriptions.
4. Tap iCloud+.
5. Follow the steps to share your existing plan.
6. Use Messages to let any family members with an existing iCloud+ plan know that they can now switch to your shared iCloud+ plan.
If a family member is already paying for their own iCloud+ plan, they can choose to switch to your plan or keep their own and still remain part of the family. When they switch to the shared family plan, they get a refund for the remainder of their personal plan. They can't keep their current plan and use the shared family plan at the same time.
On your iPhone, iPad, or iPod touch
In iOS 16 or iPadOS 16 later:
1. Go to Settings > Family.
2. Tap Subscriptions.
3. Tap iCloud+.
4. Tap Use Family Storage.
Hope this helps!
Have a great day.