This is certainly not a silly question, but it is one that is addressed fairly thoroughly in Lesson 0, specifically this video from this page. As noted there, students are to complete only the amount of work that is assigned, and when doing that work they are to invest as much time as they require to do it to the best of their current ability.

It is expected that students will struggle with understanding and applying concepts, but the homework is there specifically to provide a body of work upon which the person providing you with feedback can use to gauge your understanding of the concepts and your application of them. There is no expectation of the student meeting a certain standard - rather, it is to assess whether you should be good to continue practicing those exercises as part of your regular warmup routine.

If you wish to receive additional feedback in between, our discord chat server is available where members of the community look at each others' work in channels dedicated to each lesson. That said, the official critique program is limited to providing feedback only when a given lesson or challenge is completed. This is primarily for logistical reasons (Drawabox is a program where the students who submit homework are subsidized by those patreon supporters who don't, meaning that we have fairly limited resources on hand), but we have also found that withholding the ability to solicit feedback on a whim tends to produce students who are more thorough in checking the available resources first - so in other words, it promotes a greater degree of self-sufficiency, without leaving students to work in a vacuum.

Anyway, going back to the initial point - if you're doing more than the assigned quantity of work, don't. And if you have not gone through Lesson 0 prior to starting on Lesson 1, it is imperative that you do.