Another attempt after watching the critiques video. I only had 4 values in this because I felt like that was representative enough and I wanted to really focus on 1. Consistent shading and 2. Proportions/Accuracy. The shadows are a lot simpler in this drawing. I definitely could've added more details but I wanted to focus on the BIG picture without getting caught up in all the little things. I know the angle of the portrait is way different than the original. It's something I struggle with (just making the faces be oriented up-down) and something I'll be more cognizant of moving forward.

Finding reference images with more concentrated directional light, like the reference image included in the downloads, might make your job a bit easier here. The lighting in these images are quite diffuse, which means soft, even light that reduces shadows and highlights. You'll struggle to get a full value range in these images. This lighting is great for headshots because it's flattering but not so much for designing distinct value shapes. You might find this tool interesting to experiment with: https://www.proko.com/values. You did a great job in your second drawing finding the mid tone shapes despite the lighting challenge. You improved a lot between your first and second attempts. Keep up the good work 👍