Do us a favor. Don't keep reading.
Instead, start browsing. Flip through the book till you see something interesting. Read the articles around it till an interesting cross-reference takes you somewhere else.
Keep it fun. Try to learn something new each day. Browse through the book until you find something that makes you smile. Then set the book aside until the next time you need a break.
If you do insist on reading straight through, you'll find stuff in the next four chapters about logging in and out, about organizing your home directory, about setting up your terminal, and about shell and environment variables.
Chapter 2: Logging In