Open Settings
Tap your Apple ID name
Tap Media & Purchases
Tap Password Settings
Turn off Require Password for Free Downloads
If prompted, enter your Apple ID password
On Face ID or Touch ID devices, you may need to turn off App Store password requests in Face ID & Passcode or Touch ID & Passcode settings
If Screen Time restrictions are enabled, go to Settings
Tap Screen Time
Tap Content & Privacy Restrictions
Tap iTunes & App Store Purchases
Set Password Settings or purchase restrictions to allow changes