What you want to search is "rigged 3d model". Sketchfab offer paid models. Turbosquid and cgtrader offer both paid and free. Then what you want is a program to open and pose the models. Blender3d is free and should be able to import the files you download.

Some of my favourites (but maybe less useful for scifi, guns etc.): Even Amundsen, Claire Wendling, JAW Cooper, Sinix, Alphonse Mucha, Jorge Jimenez, Kim Jung Gi (in no particular order).

Hello Max! I think that this drawing is lacking a variety of edges, I'm mostly seeing hard and firm edges, you need to get better at making and identifying where to make soft edges, remember that learning art is more learning to see than learning to paint/draw. That skill of observation will develop by observing instructors interpret references, watching them draw and you being aware of those decisions, or at least I think I improved the most that way. As for the technique, you also need to practice making soft gradations so you can make a form turn beautifully, keep practicing the simple forms, balls, cones and you'll get better

Hi anttik, this is a nice study, I'll tell you what I personally see. Proportionally, think the guy is a little bit too short, I don't know what your goal in this drawing is, but in terms of the value/tonal composition I think it's lacking. Every form is just popping out too much, there's contrast everywhere, if you want to improve on that I highly recommend that you watch this video by Steven Zapata, he addresses this issue with the contrast priority of a statue and he explains how you can change that contrast priority depending on your subject and message: https://www.youtube.com/watch?v=A7vqD56pYfU&t=5s I would also recommend using other references, New Masters Academy has great ones (because they have great light and shadow), looking at those references from NMA and at those bodybuilders like the one you used combined will help you learn a lot!

Wow, I love these!! Very beautiful! @felipev99  I don't know if I am in the position to give feedback, but here are some things I notice: - Maybe some more indication of plane changes in the face, for example between forehead and temple / front and side of the head. You mainly make (great) use of contourlines at the moment, maybe a bit more lines within the faces would give them a more '3D look'. - I love how you leave certain lines out or make them very soft; sometimes the correct placement of just some lines is enough to describe the features very beautfifully. I do feel like some structure of those features gets lost though. - I would like to see more necks, and how the head connects to the neck. Well, It was hard for me to find things I would improve. I hope my feedback was justified. I am curious what others have to say! Thank you for sharing these beautiful drawings! -Leon