You initiated this one ok.

A post can be a reply in an existing thread or the first post in a new thread.

If you have a question that pertains to something already being discussed, then it may be appropriate to post a reply in an existing thread.

If you don't see something close, then start a new thread in the forum that most closely matches your problem.

EDIT: For example if you click on FORUM QUESTIONS and ANSWERS and see the "NEW POST" button, that will create a thread with your question.