Hi Wilp. Welcome to Drawabox, and good job making it this far. I have a fair amount to say, so I'll split my critique up into the same three sections as the lesson itself to make it easier to understand. Some of it might seem harsh, but it's all meant to help you improve. Without further ado then...

Lines

Looking at your exercises for this section, I'm fairly confident that you aren't ghosting your lines properly before you draw them, nor drawing them confidently from the shoulder. I'm seeing a lot of wobble that comes from worrying too much about accuracy, and the fraying at the starting points on your Superimposed Lines (like this: https://d15v304a6xpq4b.cloudfront.net/lesson_images/1585f266.jpg). Controlling where such a long line ends up can be hard, but you have complete control over where it begins, so this shouldn't happen so long as you take your time.

Think of ghosting a line as doing practice runs at drawing a line from point to point in a single fluid motion. You might find it takes seven, eight, or even more passes to get the feel of the motion down, but this is the kind of care and attention necessary for good markmaking. This motion should come from the shoulders (and occasionally the elbows), which are better for this sort of work than the wrist. Don't worry too much about accuracy; this comes with time and practice, and slowing down to correct your trajectory is how lines become wobbly instead of smooth and confident.

There's also a little bit of arcing here and there. If you notice that happening to your lines in the future, try deliberately drawing a slight arc going the other way. This should counteract the effect and get you into good habits. You've also redrawn one or two, which we don't encourage. If you can tell you've made a mistake, don't worry too much, and just work through it.

On the positive side, I can see that you have been fairly diligent about plotting your lines, and otherweise followed all the instrutcions, so as long as you start taking your time with the ghosting process, you should be able to improve quickly.

Ellipses

You've done a fairly good job keeping your ellipses in their intended spaces, and keeping the ellipses in your funnels exercise properly aligned to the minor axis. Unfortunately I'm seeing a lot of the same confidence issues that are present in your lines, leading to some unevenness here and there.

You're also drawing through most of your ellipses much more than the two or three times prescribed by the exercise. I think I know why: it's tempting to keep your pen moving as you repeat the motions and develop a more smooth and confident shape. But getting that in place is something that you should do during the ghosting phase. I do note, however, that this is something you seem to have ironed out yourself as you've progressed through the exercises, and the fact that you've corrected this error on your own is very good to see.

The only other issue is that there should be a more appreciable difference in the angles (width) of the ellipses in your Funnels exercises, with the ellipses thin in the centre and getting wider as they approach the edge. Try holding a pot lid or CD up with the thin side facing you and move it side to side to observe this effect in real life. (This is fairly advanced, so this is something to think about once you've mastered the more fundamental matters discussed above.)

Boxes

Your Plotted Perspective exercise looks okay, though there is one box that doesn't quite read as a 3D shape (rightmost in the second set) and I would note that it's probably better to draw a horizon line in the frame rather than using the frame itself. Your Rough Perspective is also looking pretty good, save for the line issues I've already covered. You're plotting your lines back properly, though you seem to have skipped or forgotten this step on the last few frames.

Your Rotated Boxes look pretty good, too. You've followed the instructions well, and your rotation effect is consistent and accurate save for the top-rightmost box. (I did see some redrawn lines, though. Remember, work through your mistakes.) Your Organic Perspective exercises look okay (I think you did especially well on the swooping guideline), but it might be better to keep the boxes consistently bigger or smaller as they get closer to or farther from the viewer, since this is a perspective exercise. (Again, this last point is fairly advanced, and something you'll come to get a grip on once you've done Lesson 2.)