Google virtual cam. It’s a plug in for OBS. You start a zoom call, start virtual cam in OBS under the tools menu. This makes OBS a selectable camera in zoom.
Once your OBS is on zoom, add a source in OBS for window capture and select the zoom window. Then crop and copy as many times as you need to organize that feed on your OBS screen.
We found that if you keep the zoom call on full screen and pin the feed you want to capture, you’ll get the best possible resolution for when you window capture that to OBS. Then just alt tab when you want to switch back and forth from OBS to zoom.
It’s nice too as the same mic you’re using to participate in the zoom call will be the mic you’re using on your stream. Then just pump your desktop audio into your stream so your watchers can hear the other person on the zoom call.
I’d be happy to hop on a zoom call sometime with anyone to walk them through it.