Will resetting iPhone 11 fix major Face ID issues?

You should try

1. Force restart it Force restart iPhone - Apple Support
2. if that doesn't help, backup, erase, restore

Resources…

Back Up: How to back up your iPhone, iPad, and iPod touch - Apple Support

Erase & Restore: Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

If no luck, the camera may well be broken.

There is no way for anyone to give you an accurate answer. If you have a software issue, it's possible a complete reset of your phone will work. If you have a hardware issue, it won't. You can give it a try and if it works, great. If it doesn't, you'll need to schedule an appointment at your Apple Store Genius Bar for service options --> Genius Bar Reservation and Apple Support Options - Apple

Has the front camera been replaced by someone other than Apple?