I don't understand the first question. As for the second, imagine a basketball whose top tilts ever so slightly towards a fire and then away from it. The equatorial parts of the ball will be closer to the fire than the bottom or top. Ergo seasons and cold poles. Don't forget, the poles also warm up during "summer". Just not so much as to melt the ice.
It works that way on the flat earth model too. Here's a good flat earth model. https://www.youtube.com/watch?v=Gbec8CyHf30
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