You asked us a question. "What keeps satellites from falling out of the sky?"
More than 2,500 satellites have followed the first one into space. This has happened over the last half-century. What keeps them all up? It is a careful balance between a satellite's speed and the pull of gravity.
Satellites are pretty much always falling. Crazy, right?
They fall at the same rate that the curve of the Earth falls away from them. That is if they are moving at the right speed. This means instead of racing farther out into space or spiraling down to Earth, they hang out in orbit around the planet.
Changes are often needed. They keep a satellite on the straight and narrow.
Earth's gravity is stronger is some places than others. Satellites can get pulled around by the sun and the moon. And even the planet Jupiter.
Gravity seems to be enough to deal with. But, satellites in low earth orbit can also get pulled out of their orbit by drag from the atmosphere. The Hubble Space Telescope is one of these satellites.
This does not even include the endless game of Frogger that satellites have to play. That is so they can avoid space junk and other high flyers.