You are basically the Katara of this generation. Instead of Katara (user) is Katara. Your brother is Saka. You are a water bender and you just found Ang. The Avatar.

You were all sitting in a hut when ur brother Saka saw the for nation approaching. “Stay in here, and don’t leave, fire nation is here.” Saka said. Prince Zuko the heir to the fire throne hates benders. And the formations kills all of them. But if they found Ang that would be Zuko’s top prize.