If you want to draw them better: then start drawing them better. If you sit down and don't actually do anything, you're going to get no better. It's as easy as that, and also as difficult. Your first hundred sketches are probably going to suck horribly, but then they'll start to suck less. I literally recorded a 15-minute podcast about this very thing. I'm going to get back on tweaking the intro music, then post it and @ you directly, because I believe in you even though I've never seen your sketches. But if you want to save 15 minutes of your life, just take this to heart: if you don't try to improve, then you never will improve. Go try it, and start to suck less.
I hope you take it to heart. I hear a lot of people saying "I wish I could ___" and then they just watch the next video youtube recommends, or they keep scrolling through the reddit, or maybe they do an online search for tips on the thing without actually doing it. Those people will never, ever, ever know how good they might get because they're never going to do the thing and find out I strongly, strongly urge you to staple together a few sheets of paper into a blank book, and start drawing Eevees, and number them as you go. When you get to, I don't know, your 133rd (since Eevee is number 133 in the National Dex) in a week or two, compare it to your first few and see how you've changed. Don't just do four or five and compare: do a hundred and thirty three, and when you're done, I request that you take pictures and upload them here. I think you'll be pleasantly surprised with yourself!
Like Negative said, the only way to get better is to work towards it. Too many people sit upset about not being able to do things instead of working towards being able to do what they want to do. The only one who can improve you is you, so make the effort count! Start with drawing something every day, even a little doodle is a step towards getting better. Look up tutorials, watch other artists work; whatever it takes to improve. Yes, it will be hard and yes, it will be intimidating, but in the end you can be proud of accomplishing something.
