I'm cleary begginer artist, What do you think I should learn to get better at drawing based on this?

[warped kindle]

proportions and just anatomy in general. I suggest you practice using curved/rounder lines, especially for the torso/near the waist. Cuz you draw them too straight/stick-like. Avoid using references with clothing or are drawings, and try to find ones with only underwear or body suits, like the image(u can find in devart or pinterest). the more skin the better, since youll be able to clearly see which part of the body is which :))

also stick to simple poses. You dont want to start practicing perspective when you dont understand it yet lol.