Did you go to school?
What’s pulling us down? Do you think people at the equator are standing on a vertical cliff? Do you think people at the “bottom” of the world are upside down and will fall off?
Fall off to where?
Gravity is why the apple falls to the ground. Gravity always “points” to the center of the earth’s core. Therefore, no matter where you stand on the “big ball” as you call it, down is always going to be toward the ground and up is always going to be up toward the sky.