Hello drey39,
Thanks for reaching out to the Apple Support Communities!
This page shows what to select when wanting to keep Share My Location from being changed.
Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support
To allow changes to privacy settings:
1. Go to Settings and tap Screen Time.
2. Tap Content & Privacy Restrictions. If asked, enter your passcode.
3. Under Privacy, tap the setting that you want to change.
Here are the things you can restrict:
• Share My Location: Lock the settings for location sharing in Messages and Find My Friends
If you're not seeing the correct options for restrictions, you'll want to reach out to Apple Support to look in to that and see what may be happening.
You can reach out to them here: Get Support
Cheers!