Your last post is all requests and questions.
The only statement you made about flowing bodies not curving on a round earth is demonstrably wrong. Consider the river Nile. A flowing body over thousands of miles. Are you saying it does not bend with the curvature of the earth? You are being particularly stupid today. A canal or river that flows over 6 miles should still curve, flowing has nothing to do with it, another red herring.
You still haven't read about weather so I'll ignore your protesting about wind. Unequal pressure = wind. It is not instantaneous else we'd be hit by light speed gushes of wind at every discrepancy of pressure. And that doesn't happen, so unequal pressures prevail until the wind equals the pressure and the wind ceases. If it is windy, the pressure is unequal. Wind always travels from high pressure to low.
My drawings of tubes show how pressure effects water levels. Google manometer to find out how they work and the science behind it. Go on, google that one. You'll stop asking questions that show your education ceased at high school.
Well, I guess my job here is done. You've demonstrated even to the casual reader of this thread your failure.
No, a flowing body of water does not follow the curvature of the RE. Flowing water follows the lay of the land over which it flows.
Try this thought experiment. Consider that you're floating in the Niagara River just a few inches from the Falls. Your eyes are at the water level. When you look downriver you do not see water blocking your view beyond the edge. Now consider that you're floating just after the Falls with again your eyes at water level. When you look upriver, you see water blocking your view.
There is nothing in RET (and I challenge you to find a source that argues your side) that says the surface of a flowing body of water must be shaped by the curvature of the earth.
Again, please do document that the effect you claim of low-pressure would cause the "hiding" of the lower parts of the City of Niagara Falls.