How do I get off family Apple ID and get my own

If 13 years old or older.

How to create a new Apple ID - Apple Support

https://appleid.apple.com/account

If under 13 years old, you will need to set up Family Sharing to create an ID.

Create an Apple ID for your child - Apple Support

What is Family Sharing? - Apple Support

Set up Family Sharing - Apple Support

When changing to the new ID, there may be some data loss, but you can minimize it. If syncing photos with iCloud, ensure Optimization is turned off in Settings/Your Name/iCloud/Photos and/or in Photos/Preferences/iCloud. Then make sure full resolution photos are on the device/computer. When signing out of iCloud, if asked whether you want to retain data, choose yes. Messages conversations will be lost if they are addressed to the ID. See the article below for other places that the old ID should be removed. See Winston Churchill's response in the below discussion. Also set up Family Sharing between the IDs to keep access to your apps/purchases. 

https://www.imore.com/how-change-apple-id-your-iphone-or-ipad

How to transfer all files from one iCloud… - Apple Community

What to do after you change your Apple ID or password - Apple Support