/ic/ - Artwork/Critique

I've made a full drawing after a long time without drawing properly. I want to ask there is someway to get better with messy chicken lines? Does peter han line exercise and draw a box ghosting works? Also does the size of the paper influence your drawing, I always draw in A4 paper when it's difficult to draw the face/hands/feet properly because when I draw a full size figure it gets so small (like this drawing). And drawing digital is better because you have and infinite sized paper? Also copy another person artwork, like this one, is good to learning or it's better to only copy real people? Also I don't have a good camera/scanner, but this drawing looks good? I'm aware of the hands, feet and hair that didn't look good.