With the proliferation of virtual meetings, like with Zoom, as one example, if your webcam stops working, the following article discusses possible fixes:

https://www.howtogeek.com/682516/mac-camera-not-working-heres-how-to-fix-it/

The following article also explains how to use your iPhone as a webcam:

https://www.howtogeek.com/669589/how-to-use-your-iphone-as-a-webcam/

Hopefully, you'll never have to use either article, but you might save them, just in case. Maybe the easiest fix is just to use your iPad instead of your Mac.

Jim Hamm