Well, you asked super basic things one usually finds out after playing with OBS Studio an hour or two. I, for myself, seldom answer to those threads, because while I write it, the poster already found out the answer by himself, and so my writing is of no use.
The word from the admin is not bad either - you see, almost all questions a newbie can have were already answered in the last years. You just have to find the answer. This is usually faster than any forum post, so I really suggest to improve your Google research skills.
There are not that many starter questions: "how can I present myself in a webcam", "how can I preview the recording while recording", "how can I look up something while showing something different" are one of those challenges everybody has. This is either about handling sources within OBS (which you have to find out yourself, because it's the main thing OBS is about) or about having 2 monitors instead of 1, so you have 1 monitor for the stuff you're recording and the second one for monitoring and information peeking.