One of the basic skills in art is anatomy. Although it sometimes may seem as if an artist doesn't bother about the anatomical corectness of their characters (cartoons, anime, caricature), you can be sure that they know perfectly well how to draw it if they had to: Know the rules, so you can break them all the better. 
    Unfortunately that's much, much easier said than done: Learning anatomy is bloody hard. It takes time and dedication to learn just the basics, and even established artists often struggle with it. Luckily many people have gone before us, and some of them have been kind enough to make tutorials, to hopefully make it just a tiny bit easier <3 I hope these can help you in your quest to improve your art skills. 
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  These tutorials will not magically teach you how to draw perfect anatomy. There is only o