Hi, great job! Very readable picture with clear blueish light. Nice If I can recommend something, I think you have the same problem as me - you are afraid o using too saturated and dark colours and because o that everything looks grayish and flat. Try checking values to be sure that darks and lights are push enough.

Hi, Shadow First, let me say that you don't need to apologize for bad lines. Beginner artists have this weird mentality that they should be perfect from the start. So they apologize for bad drawings, apologize for mistakes, apologize for bad lines...but guess, what? If you're doing these things for the first time you're expected to make this mistakes, you're supposed to make bad drawings, bad lines etc. Nobody is amazing when they start and if you put a lot of pressure on yourself to be you end up afraid of trying and burnout. So give yourself credit for trying this exercise and submitting it for critique. Trust me, just doing this puts you way above most of people. And if you get called out on your lines, that ok. Most artist don't critique you to put you down. They point this so you can work on that and improve. Bottom line, don't put too much pressure on yourself. If you not sure what you do, ask for help.It's ok. So on to your exercise. Your lines are a issue. But I don't really know if that's a problem you're having because you're new to digital or if it's something that happens when you're using pencil and paper too. I tried to look for your other exercises but the images were too small and I couldn't arrive at a conclusion. In both cases I advise you using more your elbow and shoulder to draw instead of your pulse. Before drawing, everyday, practice drawing ovals and long lines using your whole arm. In time you'll get more confident. Apart for the lines I feel that your drawings lack structure. the spine is twisting in weird ways and everything feels mushy. Try reviewing the movement and form of each section of the spine and try repeating this exercise with boxes instead of the the rib, pelvis and head. pay attention to where they're pointing and their sizes in relation to each other. also practice drawing cylinders and bent cylinders (remember long lines). The important thing in this section is to learn the simplified form and movement of the spine. Simplifying the other parts is ok, since later you're going to learn more about them. For now boxes are good enough. You can always try this exercise again after you study later sections. Keep drawing and Best Regards