Hey there! Great job!! Try this workout for shadows, helped me a lot https://artwod.com/blog/portrait-shadow-mapping-master-lighting-and-shadows-for-realistic-faces

I started drawing in pen without guidelines to try to improve draftsmanship and use fewer lines, and the proportions are better than expected but I am having trouble with shading. What can I learn or practice to improve from here?
Hey there! Great job!! Try this workout for shadows, helped me a lot https://artwod.com/blog/portrait-shadow-mapping-master-lighting-and-shadows-for-realistic-faces