I forgot my passcode I have facial recognition how can I get into my phone

if you can get into the phone then Back it up first

(1)          How to back up your iPhone, iPad, and iPod touch - Apple Support

then and only then

iPhone Unavailable, Security Lockout, or Disabled

You can sometimes remedy this without a computer if on iOS 15.2 or later by tapping on "erase iPhone" , but you will still need the Apple ID password. It will WIPE the phone, no choice!

How to remove your iPhone, iPad, or iPod touch passcode without a computer - Apple Support

video

https://youtu.be/7s8-zLG9ySQ

 ios 15.1 and earlier:

If you've forgotten your iPhone passcode – Apple Support (UK)

No. Face ID is not a replacement for the passcode. If you don't the passcode, you have to follow the directions in this link --> If you forgot your iPhone passcode - Apple Support