missing camera icon from iPhone home page

You have not disclosed which iPhone you are using. You have not disclosed which iOS version you are using. I will therefore provide a general resolution for the issue that you are facing (Camera app does not appear on the home screen).

Open Settings ➔ General ➔ Reset ➔ Reset Home Screen Layout. This action will return the Camera app to your home screen and rearrange the apps to their default positions.

Axel F.

Ensure that your Mac and your iPhone are using the same Apple ID and then Double Check the following settings-

On your iPhone

Open Settings ➔ Phone ➔ Calls on other devices : Ensure that this is set to ON and your Mac is listed below that. Find the listed Mac and ensure that the switch for the Mac is set to ON.

On your Mac

Open FaceTime ➔ Preferences ➔ You can be reached for FaceTime at : Ensure that your Phone number is checked. Calls from iPhone is checked.

Axel F.

You are welcome. Glad it worked out.

Axel F.

Does the FaceTime on your mac have a phone number checked or an email address checked or both? Same question for your iPhone.

Axel F.

How about signing out of FaceTime on your Mac and then signing back in again? Try that.

Axel F.