Don't render pixels of object

Hi there,

I’ve been looking for this shader element for a long time, but I can’t find it.

I want a shader that get rid of the pixels at a objects location.
With 2 cameras, I want to create a portal effect.

Camera 1 renders world 1 and if the camera tries to render a certain object it deletes those pixels. like the “no clear” setting for the camera.
Then Camera 2 will render world 2 underneath camera 1. Thus seeing world 2 through the portal.

When you go through, the portal goes away, so then world 2 is the prominent world.

I hope people can guide me to the right way.

Note:
I am no shader expert. I know very very very little of shaders.

Take a look at stencil buffers. Render Textures might be another solution.

There is also a free asset out there at which you could take a look: Unity Asset Store - The Best Assets for Game Making