If you are under 18 years of age and your device has family payment settings, you will not be able to make a purchase without parental permission. When the Ask to Buy notification appears, you can send a request to your parent's device. If the owner of the parental device confirms the purchase. If you are the owner of the parent device:

1. Go to Device Settings.

2) Sign in to iCloud under Family and select the family member for whom you want to confirm the purchase.

3) Confirm the payment.