i want to get a cash flow from art but i can barely draw a curved line in paint

Just do a lot of art and you will improve.

Try copy people you like.

Yeah there isn't really a certain way of doing art that gives your work value. Keep drawing until you find a style that's right for you and run with it.

get a good art program like gimp or photoshop

1) start drawing even if you think you suck
2) love drawing
3) keep drawing for several years even though you might consider yourself bad at art during all of them
4) don't be afraid to take notes from pro's (read: not me) or reality

Ain't no way around it, it'll take a long time before you get good enough that people will pay you for it. :I

if you want to learn art to earn virtual credits in a video game, you're not going anywhere.

your incentive right now is money, so you're already wanting to please others rather than yourself. That's not good. If you don't like what you're making, you'll never improve.