Demo level 2 . I have an issue where the head getting smaller as long as i draw the rest of the body. So i need to redraw it or draw head later. I should consider proportion stuff to make it better.

Not bad! I think you could use a little more variance in your lines -- lighter in certain places and darker in others. Like the eyes in the first portrait; I don't think they should be fully outlined. I'm assuming the darkest spots would be in that finger where it touches his face, and in areas near the neck, where the collar meets the skin. Essentially, places with shadow and where the guy clearly stands out from the background. Anyways, great work. Can't wait to see more of your stuff.