I'm always pretty skeptical of anything that offers "Learn X Quick!". Is there any reason I should trust the author of this as a good source? They even state they only started learning this stuff a year ago. I wouldn't take a course or buy a book from anyone claiming only 1 year's study in any subject, why should CS be any different?

edit: It's also hard to find the author's name to find out who they are. It's not in text anywhere on the page, only in the image of the book cover.