I think @Liandro pretty much covered it all. I think everything he suggested will help you to understand better the structure of the body from the bones up. Keep going, what you are studying is not easy, but with some practice, it will get easier I promise :)

Hey, @Anubhav Saini! Thanks for reaching out! Good job studying these complex muscle groups! Definitely a challenge, but I'm sure your effort will pay off. Overall, my major suggestion would be to identify the bones underneath and draw all the muscles as if they were transparent - that way, you can track all the origins and insertions more precisely, and this will make your anatomy studies much more effective. If drawing through all the forms starts to make your drawings look visually messy due to many lines overlapping each other, one nice thing you can do is to try and keep a clear visual hierarchy based on line quality: thick and bolder lines for the "visible" forms in front, and thinner, lighter lines for whatever is "hidden" or farther behind. Here are some more specific thoughts referring to each of the different drawings: -- - In images 1, 3, 6 and 7, the Deltoids’ shapes are fine overall, but the insertions aren’t shown, and the muscle just ends as a rounded shape. We could get away with that on the surface sometimes, but if you really want to understand anatomy, you can take advantage of your time while studying anatomy and track the muscles' ends all the way to the insertions on the bones.  - I think images 2 and 4 are the most successful ones in this group of drawings. Even though the attachments aren’t shown as I mentioned before, the overall aspect of the muscles look believable, and there’s pleasing shape design. Based on your undersketches, I can also see you’re thinking nicely about the gesture of the arm. In image 5, which is the same pose, the way the Deltoid sort of “pierces” intro the shape of the Biceps Brachii looks incorrect.  - Image 8, to me, is the weakest one in this group - the anatomy and the design just don’t seem to be working very well. Image 6 (which, I guess, is the same pose as 8 - is it?) has a slightly better resolution on the Deltoids and Biceps Brachii, but the Brachialis don’t look anatomically correct, and the pose looks a bit confusing to me (at first glance, I thought it was a back view). If possible, I’d re-do these ones entirely applying the idea of drawing transparent and showing the bones underneath.  - In 1, the shapes of the Biceps Brachii and Brachialis don’t seem to be bent properly - it looks like they’re being pushed upward as if the Brachioradialis was a large volume underneath, which isn’t accurate. Image 3 (the same pose) looks a bit better!  - In image 9, the Biceps Brachii looks a bit too small, and I also feel a bit of the “snowman effect” in the way the shapes are designed. When thinking of the muscles shapes, consider drawing them more asymmetrical and dynamic (you can refer back to the "How to Draw Gesture" lesson, from the Figure course, in case you need a refresh on this matter). Image 7 looks like an upgraded version of the same pose to me - both size and shape look better resolved when compared to 9. But one thing I like about 9 that 7 doesn’t show is the cross-contours - they do help a lot in indicating the volumes. Although I don't think you need to draw so many cross-contours - usually, one for each muscle section works fine. When it's a longer muscle, such as the Quads of the Erector Spinae, we can add a pair of cross-contours, depending on the pose, but I think that's not the case for the Deltoids or Biceps. -- As another major suggestion, in case you haven’t, I’d recommend starting your studies with the exact same references as the ones Stan shows in the anatomy lessons. Studying the same poses of the example videos allows you to check your work more easily, as you have immediate reference and demo provided by the instructor. Then, when you're done with those, you could expand your practice by chasing other references to try on your own. Finally, one extra recommendation: I’d advise studying the Deltoids and the Biceps separately first. If this is the first time you’re learning them, they can be better understood if studied independently in the beginning. Once you’ve already studied them separately and feel comfortable enough with drawing them individually with anatomical accuracy, then it’s fine to go ahead and study these different group muscles conjoinedly like this. Hope this helps! Please let me know if I can help you with anything else. Keep up the studies!! Best of luck!

@Steve Lenze @Liandro @Proko