My camera has not worked since the last update what do I need to do to get it to work now

First let's see if the camera was accidentally turned off.

Settings > Screen Time > Content & Privacy Restrictions > Allowed Apps = Is camera turned off, if it is turn it on.

If camera was not turned off, Force Restart your phone. See the directions in this link --> Force restart iPhone - Apple Support

the camera was on, and I did a Forced Restart, but it still not working on my iPhone 8 +. What to do now?

Schedule an appointment at your Apple Store Genius Bar or Apple Authorized Service Provider and have them check out your phone.