Hello and welcome to Drawabox! I hope you're ready for what's coming next and you'll have no trouble reaching the finish line. Here's my critique for each section:

Lines section

Some of your lines may miss their mark this early on, but that will improve with practice. They're smooth and confident, and that's what's most important right now; I'd say you did an excellent job.

Ellipses section

You're drawing through your ellipses and they're consistently hitting their boundaries. As you improve, you'll want to start drawing through your ellipses only twice, and hopefully only once, eventually.

Boxes section

You've done a great job with these as well, especially considering they give a lot of trouble to beginners. Your rotated boxes, though one half is slightly stretched compared to the other, show a great understanding of how boxes turn in 3D space. Some of your boxes in organic perspective are flawed, but again, this is to be expected this early on: that's what the next lessons will be for. The main thing I have to point out, however, is that sometimes you'll go through the same line more than once if you don't nail it in the first go. Avoid that going forward: if you mess a line up, just move on to the next.

Overall I think you're more than ready for the next lessons. Remember that you're meant to complete them with a black 0.5 fineliner, so I'd advise stocking up on those. Don't forget your warmups, and good luck with the 250 Box Challenge!