I guess people on this web site are so used to arguing with one another, that they have lost the ability to discuss something, that doesn't require a debate or argument.
I asked a simple question and not only can no one answer it, they don't even seem to be willing to discuss it.
I'm not in a Monty Python skit. I'm not looking for an argument. I'd just like to hear a rational explanation of how the various "secrets" of the flat earth were learned. If you can't go to Antarctica, how does anyone know there's an ice wall hundreds of feet high? How does anyone know what the sun and moon are made of or how large they are and how far away they are? How was it learned that NASA is acting as a military force to keep people away from Antarctica? Then there are so many more questions like these.
How do people know this stuff? Just by critical thinking?
Don't be a hypocrite, you posted this on the first page of this thread.
That's not "proof" of any sort. If this is all you've got, I'm going to say, Busted!
To answer your simple question, Username traveled to Antarctica and was denied entrance. He's posted about it many times over the years. I thought he'd answered you in this thread, but it's in the why would the govt trick us thread.
Your other questions about the conspiracy - "how is so much known about the various conspiracies maintained by governments to keep the public from knowing about the flat earth?" and my answer to that is that there is not "so much known".
Also, different FE have differing theories about what the sun and moon are made of, how far away they are, etc. The problem with trying to get answers on this forum is the same with most forums. The people who would have answered your questions have moved onto other forms of social media. Every thread, no matter the good intentions of the OP, is soon flooded with RE insults and derailments. There are people on this forum, who have been here for years, who are so afraid someone will mistake them for a flat earther that they make sure to turn any discussion into a poop flinging fight.
Anyway, those of us left here from the good old days are always happy when new people turn up and seem willing to have conversations. If you stick around, you will learn who to scroll past and who to reply to. Maybe you will even discover the bowels of the forum and have some fun.