family is managed by someone how can i remove my self from this

Hi there,

see this on how to remove yourself from a family sharing group

Any family member age 13 or older* can remove themselves from a family group. If you have Screen Time turned on for your account, the family organizer must remove you. 

On your iPhone, iPad, or iPod touch

1. Go to Settings.
2. Tap Family. If you don't see Family, tap your name, then tap Family Sharing. 
3. Tap your name.
4. Tap Stop Using Family Sharing.