Flat Earth theory was disproved thousands of years ago, but even so, there are still people who still believe in a flat Earth. Some people who defend flat earth are just trolls, only wanting to pretend to believe. Others, however, truly believe the Earth is flat and we are being misled.
Why we would be misled is anyone’s guess. A round Earth was proposed way back in the time of ancient Greece. It was later proven by using simple sticks to show the sun at the same point in sky, at two different locations, produced two different length shadows.
High altitude cameras and even satellites in space looking back at Earth never capture all of the continents in one picture. If you get far enough away wouldn’t you see them all in one picture? Or at least rotate around to the other side of the flat Earth and see the bottom?
The moon circling the Earth shows that it cannot be flat, from the lunar eclipses, to the visibility of only one side of the moon since it is tidally locked. People in the same time zone in the northern and southern hemisphere should see different faces of the moon, instead of the same one.
Simply watching ships go out too see debunks flat Earth theory. As the ship goes out it slowly “sinks” as it travels around the Earth. If the Earth were really flat, the ship would simply keep getting smaller, with the total ship in view the whole time.
If you really want to believe the Earth is still flat, that’s your prerogative. Just don’t try to push it into textbooks or make it a possible acceptable theory. Keep the stupid to yourself, don’t try to pass it off as fact.