For most artists humans are the most difficult, in part because we are more critical of their appearance since any flaw is immediately apparent to us(we constantly look at people and know what they should look like). The best advice is practice. You probably don't draw a lot of people because you don't think you're good at it. Well draw them anyway. Use reference photos and draw. The first 5, 10, or 20 drawings will likely not be that great, but each time you'll learn, and you'll get the feel for how drawing a human should be. Watch videos of people drawing humans and observe their process. If you really want to draw people well, practice and you'll get there I promise.
Look forward to seeing some cool drawings from you!