what can you tell about charlie's character and qualities?

Charlie is a 32-year-old mentally disabled man who resides in New York City. He works at a small shop called Donner's Bakery where he is the Janitor and Delivery Boy. He always has an eager and happy attitude and when he enrolls in a literature class for mentally disabled adults he excels (at least in comparison to his peers). He undergoes a surgery to become more intelligent and soon after gains a massive amount of knowledge becoming a genius in a matter of days. However, his maturity and intelligence are not parallel and this becomes a large internal conflict for him throughout the story.