Yes you can do what you mention in OBS
HOWEVER
there are lots of completely different ways to get the remote video (and audio?) into OBS, each with its own Pro's & Con's. so, I can't recommend how to do accomplish sourcing the remote video. Others may recommend certain approaches, but without more info, all you'll be hearing is what they use/what they like, not necessarily will be good for you
Personally, I'm of the mind to keep it simple in the beginning (crawl, walk, run. don't start by trying a marathon)
There are tools/plug-ins like OBS.ninja... ymmv or the commercial Zoom, Teams, Skype, WhatsApp, etc....
The one thing you will likely need to be attentive to, is that by having different video sources (local camera plus something remote) is audio and video sync. Audio coming in via same local camera will often be sync'ed by default. But say you use a USB or audio cable connected mic to PC, and a separate camera for video only.... in such a case you have to manually sync the audio yourself (not that hard, but not an automated step). Then speed of light isn't that fast, and then your PC has to process remote video.... so you may have more sync issues to address
just things to be aware of