Then which coutries exactly are on the eastern ridge and the western ridge? And if Earth is flat then why hasn't anyone tried rock climbing to the other side of Earth?
There is no 'eastern' or 'western' ridge. A number of people have tried to find the edge, but most have not returned or just didn't make it.
What about the scientists?
They're just chillin'. They are not interested in searching for the edge of the Earth. They have other research interests and thusly never think of climbing down the side of the Earth.
They are not chilling, they are freezing. And if the Earth was flat, then they would barely stand since the wind would be so strong that would pull them to the edge and out of the Earth. Remember, the Earth is moving up, so the air is pushing toward the ice wall and then out of the planet.