You have a few questions there. All of which are adressed in the book / course.
Changing the order, you should start with an easier book. You want increase you success experience. The PRWMS suggest a non-fiction and non-technical book of about 200 pages. This gives you a structure material to read, and the information density is not too great.
That said, yes you can use this very big and important to you book. You just have to be very easy on yourself. You are going to do a lot of learning as you go about activating your first few books. You might want to try some easier material. Something without any pressure associated with you having all the knowledge in the book. Pressure / stress is a killer to the whole system.
If you real large technical material, the PRWMS says you are to treat each chapter as if it were a book in itself. You often hear that you should PR the entire book. Wait at least 20 minutes. Then PR 3 chapters. One before the material you want to learn, the one you want to learn, and the one after the one you want to learn. There are some good reason for this. Of course you can't do it for chapter 1.
Then you do activation passes on the current chapter you want to learn.
My advice is to follow the course and do something less challenging and less stressful for your first 5 books.
Sending love,
Iam2 
