Drawing basic forms is not as intuitive as it might seem at first glance. It looks simple, but there is a lot of nuance to it. A lot of art books and courses don't pay enough attention to really nailing down how to do boxes and cylinders correctly, and if you move forward without a solid understanding of those things, it will plague your drawings. I was thinking about posting some threads to help with this very thing. Let me know if you're interested.