I forgot the passcode for my iPhone, what can I do?
I forgot my passcode for my iPhone 11, what is the least complicated way to restore or reset the phone, that will actually work?
iPhone 11
See this support document -> If you forgot your iPhone passcode - Apple Support
Bottom line is you must erase the device. With newer iOS versions (iOS 15.2 or newer) you can erase the device from the device itself, see -> If you see an iPhone or iPad unavailable message or Security Lockout screen - Apple Support
For older versions of iOS use the instructions in the first link above to erase the device with iTunes or finder.
Erasing the device is the one, and the only way to reset a screen lock passcode.