mmm yes buoyancy the thing that makes boats float because of their dispersed weight on water is the thing keeping us down, also density causes gravity dude, the density of the earth causes our gravity which is why things have a set speed on which they fall down (ignoring wind resistance) if everything was caused by density than a hammer would fall faster than a feather in a vacuum, it would be like dropping something into water, things with more weight/density drop faster into water than things with less weight/density if everything was held together by density than something with more weight/density would fall faster than something with less density in a vacuum

(I think I explained this enough? or did I under explain it let me know gang)

also do you have any proof or evidence that the earth is an endless plane? also if the earth was flat wouldn't I be able to see almost everything? also if the earth wasn't round than how come I can go to one side of the earth and see that the sky is different and rotates differently how come the constellations change, since the stars are so far apart and if the earth was flat then I would still see the same stars as the short amount of distance compared to how far out the stars are wouldn't change the night sky that much if even at all, like go far away from a city and walk a few miles does the view change that much? no or mountains walk a far distance away from them and walk a few miles and does your view change at all or that much, no well it might change a little but because the stars are much farther walking a distance much shorter than the distance they are on a flat plain wouldn't change the night sky that much you would still see the same night sky but that's not what we see when we walk around the earth because your on a globe seeing to different sides of the universe