The warm-up section contains exercises designed to target basic technical skills that you will need to master at this level. Additionally, it is a great place to get limbered up and ready to work on repertoire. The Etudes section contains pieces that are a cross between repertoire and straight-up technique pieces. They can often make a good bridge between warmups and practicing repertoire.
How much technique you do in a given practice session depends on your goals and time constraints. If you have the time, I would advise doing a thorough warm up with material from each of the three sections. If you are limited on time, do enough to get warmed up before proceeding to repertoire.
These pieces are the bridge between the technique and the repertoire sections. They will include technical elements that show up in short pieces that reflect what you are likely to find in the longer repertoire pieces.
This is the meat of the book/course. This is where you will encounter new challenges and expand your skills.
Here are some important theory concepts for this level. Even though this isn't playing directly, it is still an important component of your musical education. Having an understanding of these concepts will improve not only your overall musical knowledge, but your sight reading ability as well.