I found some sketches I did when I was sixteen. I do know that I had a problem with proportions, and often the nose or something would be too long or too small, or something along those lines. I also seem to recall having an easier time with faces facing a certain direction for some reason. What helped a great deal was looking at photographs or comic books and trying to duplicate the pictures that grabbed my attention. "Trying" being the operative word. Occasionally I ventured out into sketching things in real life, or from my imagination, but not very often. One thing I know I could draw back then was eyes.
I don't think I attempted scenery that often.
I think I had more fun with the comic books.