Creating a Client based server Unity2D

I'm creating a program where a dungeon is randomly generated and shown on one computer but on another computer it is shown as a black screen. When someone on the first computer clicks on a section of the dungeon it is then shown on the other computer.

I have made the dungeon generator but I was unsure as to how I should make the program communicate with the second computer. I have no experience with networking on Unity.

I was thinking along the lines of having the first computer (The one with the full image shown) being the host and the other computer (The one with the black screen) connecting up to it. I have no idea how to do this though.

If any of you are curious as to what I am doing this for it is for a dungeons and dragons program so the dungeon master can have the first computer and can show how much of a dungeon can be visible to the players who are on the second computer.

Thanks.