Well, I guess you will have to do some research. There are videos and articles and even podcasts on Bitcoin online. Many are already mentioned above. If you try to search for some good old threads here, you will also find a lot worth reading. There are also new ones, although it is getting harder to separate the wheat from the chaff lately.
As to engagement, if you have something worth contributing, then make a reply. If you find a discussion not worth participating, then skip it and look for another one more intellectual. There are countless of threads here.
DYOR. That’s the first step you should do so you can acquire knowledge about bitcoin. Although bitcoin is quite complicated, but with due diligence and passion to learn, everything will become clearer to you as soon as you completely understand bitcoin. And by participating in the forum discussion, it will also pave way to bring additional insights about bitcoin. But make sure if you decide to join the discussion, aside from asking questions, at least you can be a good contributor too so that other newbies will also learn from your post. It may be hard in the start but you’ll get used to it especially if you do it with high passion and enthusiasm.