Because everything in our lives hinges on the answer to that question. If there’s no God and no intelligent creator, how does human life have any meaning or purpose? What’s the point of our lives? If there’s no God, death is the end with no hope of anything else. Who cares about morality or ethics or being a good person if there’s no God? We’re just evolved animals who exist from random results of evolution.
But if there is a God, everything changes. Now there is meaning, purpose, hope, and a future. Randomness and evolutionary development does not provide that-our lives would be totally meaningless in the grand scheme of things. But if there is a God, our lives and our work do have purpose and meaning-something every human being wants. And this God has something to say about how we treat our planet, organize our society, and live our lives.