I can’t reset my iphone because i forgot screen time passcode

If you are using iOS 13.4.1, see this up-to-date article:--> If you forgot your Screen Time passcode - Apple Support

Regards

Giulio

And if you’re not able to be running 13.4.1, back up, erase, install the most recent iOS for your device, set up as new, and do not restore any backups, as restoration will also restore the screen time passcode.

An iPhone 7 can run iOS 13.4.1, though.