The best way to improve your drawing skills is to make ‘drawing’ a habit.
Practice drawing the same object/scenery etc several times.
Try to observe the meticulously detailed drawing to learn.
You can begin with, drawing shapes and then move to life drawing-nature, animals, humans etc.
Join drawing classes.
If you are absolutely new to drawing it may take you more than a year to learn how to draw. However, if you are aware of the basics, you can pick up as early as in 2-6 months’ time.