I believe they are saying to use OBS just for screen capture, then use that feed as the 'camera' input for whatever video chat application you are using

hoserhobbes covered what I meant.

OBS creates a virtual webcam you can use as input for whatever video chat program you're using. In OBS you can switch between and composite "sources" including your screen, media files, actual webcams, etc.

There is a slight learning curve but it's incredibly powerful and there's tons of tutorials online. You also have a lot more control over what you're streaming than you do in discord. Sharing your screen is fairly easy.