Okay sweetie, so the Alma-Ata Declaration is a very important document that a lot of grown ups wrote in 1978.
It talks about how every person in the world should have access to good healthcare, no matter where they live or how much money they have.
It also says that people should be able to get help not just for when they are already sick, but also to prevent them from getting sick in the first place.
The grown ups who wrote the declaration wanted to make sure that everyone in the world had a chance to be healthy and happy, because they believed that's what all people deserve. And that's a really nice thing to believe, don't you think?