Child monitoring
How do I check my child’s activity on apps when he is signed up as my son?
iPhone 12
Apple support has an article online (link below) that may help:
Seems Apple suggests you:
Use Family Sharing to provide parental consent for your child's existing Apple ID - Apple Support
Eg: Article suggests you can "Choose whether or not to enable Ask to Buy and Location Sharing for your child".
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More info:
How to: Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support
How to: Manage App Store purchases, subscriptions, settings, and restrictions on iPhone - Apple Support
How to: Prevent in-app purchases from the App Store - Apple Support
How to: Set up Screen Time for a family member on iPhone - Apple Support
If needed:
Family Sharing website
iPhone info. / support / contact:
iPhone - Official Apple Support
All the best :-)