I lost the camera app on my iphone

Hello,

Restore a built-in app that you removed

1. Go to the App Store.
2. Search for the app. Make sure that you use the exact name of the app. Find the correct name of built-in apps.
3. Tap to restore the app.
4. Wait for the app to restore, then open it from your Home screen.

More info here:

Remove built-in Apple apps from the Home screen on your iOS device with iOS 10 - Apple Support

You cannot delete the Camera app. Go to Settings>General>Restrictions and see if you have one of those on. Also, check Control Center by swiping upwards and see if the Camera appears there.

You're welcome! Definitely let us know if you have any further questions!