Its looking good, but you need a curve at the bottom of the helmet, look at the picture I have attached.
About your render, change the background environment, don't use black, use a light tan or semi-white, very light grey, just avoid black.
Add a basic three point light system:
Key Light (this will be your main light)
Fill light & a backlight
Check this tutorial for a 3 point light setup:
https://www.3drender.com/light/3point.html