If you don't know what to draw or if you have trouble drawing things, I think the best thing to do is to observe other people's artwork, like the ones on here. You don't have to look at "masterpieces"; look at art that has things you haven't drawn before. If you think carefully about how people draw certain things, and work step-by-step, then you'll be able to draw what you couldn't draw before.
Similarly, using reference photos to get ideas and as a basis for new drawings helps. You should make your own spin on whatever the photo you use features, though.

I think you could try those if you want to draw new things. So keep experimenting, since these kinds of strategies helped me learn how to draw in the first place!