Why did people in ancient times believed that the Earth was flat?

Previously, people did not have the opportunity to look down at the earth, from space. Didn’t swim around the seas and oceans to understand the whole geography. They saw the horizon around them and did not go far. If you live like this, then of course the idea of the earth will be just like that. But if a person begins to have questions, then he begins to study everything thoroughly and will certainly find out what’s what and in the end he will see his place of residence with all the details. This is how geography, astronomy, etc. arose.