How do I get my pictures to look like this?

alot of practice,lessons and equipment :3

practice, practice and even 더 많이 practice! I can't do it like that (yet) and I always get so frustrated ^^"

Well of course lots of practice and also that pic looks like the person drew it on the computer so it depends on how well 당신 can draw on the computer, what system they used like Paint sai 또는 Photoshop.
When 당신 get the hang of drawing the colouring is different because there's many ways of colouring and shading.
Also 당신 could go on 유튜브 and look at tutorials 또는 speedpaints to help 당신 get an idea of how to and keep trying you'll get there sooner 또는 later 또는 something like that because everyone has their own kind of art style

they probably have the help of a computer....

practice.