Try to find a reference that you want, it can be from Pinterest or an app called "easypose", these will help you improved more on anatomy and you can draw with the guidelines first, or you can watch some artist on YouTube to help get learn on each fundamentals of the anatomy and poses. I recommend you to watch Marc Brunet cause he's a great artist teacher that teaches anatomy and poses. Also, Sinix Design who teaches also anatomy. This is what I did as a beginner artist (still learning on anatomy)
U must got out of amateur level before achieve further, but... I can teach u cuz after reading ur comments, I found out we have the same technique, same goal yet same issue.