Heya Fluxbugs! This is definitely the right board. :)
The purpose of the longer sessions is to flesh out your studies. When you're doing the 30-120 second gestures, they're considered warmups that help your body and brain loosen up. As your classes progress to 5-10-20-30-60 minutes, the idea is to do more detailed works.
You can opt to start those as you have so far, with the line of action and basic structure as a base, and then start working on capturing the details on top of the base. Some people find this helpful and can create a more detailed figure.
Others take a different approach, where they try to loosely sketch what they see and then get more detailed and flesh out the figure. For example, they may start with a very faint line of action and very faintly lay out the basic porportions, or they may skip this entirely and just start drawing. The end result is a recreation of the reference image as much as they can during the time they spent on it.
So in short, gestures are mostly warmups and serve as a potential base, but longer studies are meant to encourage you to draw a more completed image.
It can be helpful to try and focus on specific goals here. "Draw what you see" is an incredibly broad goal, but if you narrow it down to "This week I want to focus on getting proportions right", then you can spend that time trying to focus on that. And next week you can change your goal to "I want to focus on making my figures fluid/lively" and so forth. It also helps to switch it up - this week it's full body figures, next week could be animals, hands and feet, or faces! :) Keeping it interesting gives your brain breaks and makes practicing more fun.