First Person Phone Camera Effect

I’d like to add a phone that can see what in front of it kind of like the game Dreadout but I’m not quite sure ‘exactly’ how that effect is achieved. How would I go about doing that? (New to Unity)

Uhm.

A camera object in the phone camera position and a spot light with the origin near the camera.

The camera background and the ambient light should be black. I’m not 100% sure with that last sentence.