Title of first chapter

What we will do in this chapter:

stuff

more stuff

talk about other stuff

play with stuff

Section1 title

Section2 title

Usually some introduction

on all the aspects of stuff.

Section2 title

In-depth discussion

Explain concepts.

Section2 title

Maybe some examples

And a hint to the next section of the chapter.

Section1 title

Section2 title

More stuff

More stuff

Section2 title

This is the second subsection of the second section of the first
chapter.

Add as many sections and subsections as you want.