I need to unable family sharing

Check this article on how you can stop family sharing, if you are the organiser, or leave the group if you are not the organiser.

Leave Family Sharing - Apple Support

If you are the Organizer of the family sharing, then you can disband the family members.

Open Settings ➡️ Apple ID (Your Name at Top) ➡️ Family Sharing ➡️ Click on your name ➡️ Stop Using Family Sharing.

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