Learning is done solely internally. It is not simply acquiring information, but determining the principles and processes that created it.
Remember that questions are merely a luxury. You already know all you truly need.
Confusion is a great place to be. Never shy away from being confused. You become confused when your habitual approaches to solving a problem fails. You are forced to find new methods and seek new solutions.
There are some things that are necessary to learn first before worrying about others.
The history of a subject will predicate the actual topics themselves. Learn why the founders created the subject and you will tap into the same reasoning processes which they used to build that subject.
In doing this, your progression will be quite smooth.