In our education, we are told that the Earth is a sphere because it is a sphere. It would be wrong if our educational system were to teach us that the Earth is flat.
Flat-Earthers claim that our educational system is a form of propaganda & indoctrination. In reality, we were told Earth is a sphere because it is a sphere. It would be misleading if they told us other than that. Propaganda & indoctrination is what is actually happening in flat-Earth communities themselves.