How do I reset the settings passcode ? Cause I forgot it

Sorry -- and also sorry about this reply. See the following from Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support

If you can't remember a restrictions passcode that you created on a previous version of iOS, or you forgot your Screen Time passcode, you need to erase your device, then set it up as new to remove the passcode. Restoring your device won't remove your old passcode.