Newb: 3 cameras plus Laptop built-in camera?

Hi all,

I am using two BM Studio mini cameras as well as an Aida fisheye camera to record into the Mini Pro Iso. So far so good. I would now also like to add my computer's built-in camera to feed into the switcher. I have the computer connected via HDMI out and I get the desktop beautifully. However, I don't want the desktop recorded - as I have my notes displayed there - I want the camera to be used. Is this possible? I use OBS as well, but whenever I put text on the screen it records that rather than me.
I also have a Sumo Atomos that I use as a monitor.

Thanks for your help!

You would need some software to use that camera, and then Maximize that software to fill the screen.