Hehehe….. Did someone actually tell you nobody has ever flown around the earth pole to pole?
That’s why you should check your facts before believing conspiracy theories! A good place to start is by going to Snopes.com to do your fact checking.
Not only do some satellites pass “underneath the Earth” to see what’s really down there, so have many airplanes. Furthermore, people live down there, past that “wall of ice” at the South Pole.
Here’s a picture of what it looks like for real.