It's promising, but way too short. You also made a few basic grammar mistakes, like not starting a new paragraph when changing speakers. It's also pretty vague, but I understand that it's only the first chapter.

Try writing a little more and making the next chapter have some more meat to it, explaining a little more about what the situation is and the back story. Your writing is pretty good, don't give up! I'd like to see where this goes. :)

An intriguing first chapter, I'll look forward to reading more. :)

Update soon! =)

Well, there isn't much to review in this first chapter, but it's Sokka/Zuko so it can't be too bad, right? I'm looking forward to seeing where you take this and learning how Zuko ended up in the care of Sokka :o)