How do I remove myself from Family Sharing?

You can change your settings for Family Sharing or leave the Family group, as explained in this article:

How to leave or remove a member from a Family Sharing group - Apple Support

"Unwanted Settings: Recently got Family Share but. Don’t want it.Can I uninstall it"

-------

Leaving a Group:

Show this to the Moderator: Remove someone from your Family Sharing group