Answer: "He" is the person who succeeded despite the doubters.
The context seems to be a situation that seemed impossible to most people, but one person dared to try, even when someone scoffed and tried to discourage him.
The alliteration is the repetition of s-sounds in "someone scoffed"
Explanation:
It would be too obvious for me to write the entire letter for you, but I'll include a list of points that you could include in your own writing style:
* Thanking Lee for his letter, and saying that you are happy that he is having a good time.
* Telling him roughly what you're studying at school (without being boring).
* Write about what you would like to do when you leave school.
* Finally, say that you miss him a lot and look forward to hearing from him soon.
