There have been a number of posts for and against a flat earth. Here are my two cents.
Do flat-earth'ers recon the earth rotates?
If so how is Coriolis force explained?
And it’s easy to see for yourself… pull out a plug in the northern hemisphere and the water will most often drain out in a counter-clockwise direction, then go to the Southern hemisphere and it does the same in a clockwise direction.
That is also why cyclones rotate clockwise in the southern hemisphere and counter-clockwise in the northern hemisphere.
This phenomenon occurs as the outside of a sphere, rotating on its axis, has different surface speeds.
Air or water moving perpendicular to the rotation is either left behind or sped up by these different surface speeds (depending on whether north or south of the equator) and this sets up the rotational motion.