The general idea at the moment is read the book, and as you have questions you register for the forum and ask. More of an interactive approach, much like a school.
Bill is correct. The e-book is there to provide a basic introduction to each of the topics it contains. As such, it is intended to serve as a knowledge platform upon which the reader is expected to build through a combination of research on the Internet and interactive exchanges with the members of the AAC forum.
I do hope you will decide to register with us so that you can benefit from the broad knowledge-base represented by the membership of the forum.
The material in the e-book is particularly suited to those wanting to start out in electronics and gives the student the resources to develop the core skills. There are areas that are missing but that is a by-product of the fact the e-book material is an incomplete continuous piece of work. If there is something you don't understand or want more assistance with, then feel free to sign-up and ask in the forums. That way you will get help specific to you.