Having trouble coming up with something to draw? No worries - while you'll eventually learn how to start from a tiny seed of a thought and gradually nurture it into a complex concept to explore through design and illustration, it's perfectly fine not to be there just yet.
For now though, here's an idea that might interest you.
Alien Red Light District
Picture the seediest corner of an alien world, and design it. Think about architecture, atmosphere, lighting. Humanoids are fine, but no humans. Doesn't have to be high-tech! Think about more than just the exposed skin - consider how they're going to be marketed (billboards, holograms, large displays, etc), what the clientele would look like, and even how well maintained it would all be.
Pentel Pocket Brush Pen
This is a remarkable little pen. Technically speaking, any brush pen of reasonable quality will do, but I'm especially fond of this one. It's incredibly difficult to draw with (especially at first) due to how much your stroke varies based on how much pressure you apply, and how you use it - but at the same time despite this frustration, it's also incredibly fun.
Moreover, due to the challenge of its use, it teaches you a lot about the nuances of one's stroke. These are the kinds of skills that one can carry over to standard felt tip pens, as well as to digital media. Really great for doodling and just enjoying yourself.