Hey!
nice work so far, but your shading is too rough, and you only shade the top piece while the corners of the face should be shaded too! And the head part of the robe is too wide. Now, i'm not really experienced, (also i'm not sure if i like the highlight on the shoulder) but here it is, too lazy to fix it again
Before
After
You will need to fix it again, i'm just making my point clear, not to make it look good, as you are the one who need to make it look good