Hey there nice drawing! I really like ur concept and draftsmanship! Your work can use a bit more anatomy tho i suggest watching proko's vid on robo bean and landmarks since theyre pretty important. I think the main problem here is that the ribcage is too close to the pelvis (even though its slighty foreshortened its a bit too exaggerated) Posing at forst can be really tough so i suggest you to find some simmilar reffrences to help you ! Heres a reff that i found that is pretty close to the pose ur drawing and what i think the body could look like (the green lines are the legs which i have not studied yet so dont follow it too much since it might be innacurate) My last tip is for you to post your work at the proko community section since it will make more people find you easily! Hope this helps^^