well it depeneds on what you want to draw/improve! Do you want better proportions, more realistic, animations, ect... wha do you really want ti draw?

I'm not good at any of that stuff but like they said shading and highlighting is key also use a ref and don't just post it in on an hour. just look at the picture and ur drawing. Maybe put it aside for an hour or two then look at it again. One last thing using shapes like if ur drawing human, then sketch it out(same can work for any drawing)

also ty for following