cant add the camera the inspection support network app

Force restart your phone:

• Press and quickly release VOLUME UP

     then

• Press and quickly release VOLUME DOWN

     then

• Hold the SIDE button until an Apple logo appears (15-30 seconds), ignoring "slide to power off" if it appears

The operative word here is QUICKLY; and try it a couple of times, the timing is a little tricky. If done correctly this will always work unless the phone has a hardware problem. 

If that doesn’t correct the problem, delete the app, restart the phone again, and add the app back.

And if that doesn’t fix it contact the app developer and have them fix their app→How to contact an app developer - Apple Support

Open the app and try to take a picture. It won’t give you the option to use the camera until the app tries to use the camera.