I have been reading through threads for a few days. I saw the one you are talking about.
Nothing to miss there. He seemed like he wanted trouble for lack of a better way of saying that.
You can start threads once you reach 20 posts, in the meantime you could make a thread in the introductions area or just get chatting in some other
threads 'til you hit the 20 post requirement.
Just for a little more info, once you hit 20 posts you just click Forums at the top, then click the correct sub-forum for your thread topic, then look
for the plus button you saw earlier to write a thread.