I think that in order to start, you need the basics of drawing, try reading different articles on this topic or go to courses, start with something simpler, for example, by drawing hands or fists. I can advise you this article https://wowpencils.com/how-to-draw-fist/. There are also other drawing articles here, so take a look
Dear someone'
my name is sk8 and I want to know how to draw a person sitting down in a bike
my name is sk8 and I want to know how to draw a person sitting down in a bike
Print a picture off the internet and then trace it