I'm not sure what you are asking. An internal conflict is one that a character has within himself. So an internal conflict would be one that Charlie has to deal with himself, such as his struggle against his loneliness. Perhaps you mean an external conflict that Charlie has with someone else or something else in the story. One external conflict he has is trying to fit in society. He still doesn't fit in even after he becomes a genius, and he's still lonely.
INTERNAL CONFLICT: doing what is right. Acring upon the morals he has been taught.