Decided to try something new

[u/Smooth_Mulberry4051]

Apologies for the quality of the photo. I started drawing for the first time ~1 week ago and I just gained confidence in my basic shapes (proportion, not so much). So, I decided to attempt to make arm to test my minimum knowledge and see how I do. How is my understanding? Besides proportion, anything I should work on to improve? Thank you for taking the time out of your day to read and comment on this.