How to make a camera screen on my camera model?

I’m making a small game in the same style as Outlast as a side project for school.
And I need, just like in Outlast, a working screen that displays what my camera model is seeing.

So I have a second camera that needs to be displayed on a 3D model.
I know it’s possible in Unity because I have seen it before, but absolutely no one has a tutorial about it.

To map a camera’s view to a polygon or polygons in the world, you need Unity Pro.

If you have Unity Pro, then look here…

Look into render textures. Set a camera in front of your gameObject camera, set it’s render texture, then slap that render texture on your camera’s screen model. You don’t need pro.