I'm not the best at playing basketball..
Do you like to play basketball, though, even if you aren't great at it.  It is so good for exercise, and it has a limited amount of contact as well which makes it safer than some other sports.
That's true. Sports like football are really dangerous. So what is the main idea of basketball? 
Well, most of the time it is played 5 on 5, but if you don't have 10 players handy you can play with as few as two people, but the goal is to shoot a basketball through a hoop slightly larger than the ball.  It takes a good amount of skill, but still fun even if you aren't too good at it.