Are we supposed to pick what we want to do while filmaking?
No, this is just to show you how different people are involved in a production and how many different aspects there are to consider when making a movie. Notice all the different managers and directors.
Anyone who's ever done a small project with 10 of their friends knows how hard it is to actually coordinate just those few people. It's why it takes real professionals to coordinate the hundreds of people that make a movie happen.
In that chain of command link, we're looking at having some notes and information on every subject you see in red there.
If you see anything you have solid ideas about or are good at, you can make a note of it and look through the books to find that information. :)
There are a ton. My only camera experience is my school's BJC and it was very hard to coordinate there. I get it.