Using this model, wouldn't that make the Australia's amount of sunlight received in their summer greater than that of America's summer? Also, how would you explain 24hr sunlight in Antarctica during the southern hemisphere summer?
Also also, can you explain how the Earth's magnetosphere works in a flat earth model?
The topic of Antarctica is plagued with misinformation by various governments. It is best to be skeptical of any of their or their scientists' claims. Hence the 24 hour sun theory is fake news.
Regarding the magnetic field , there are 2 prevailing theories.
The simpler one is that the earth's magnetic field is similar to that of a disc magnet.
This model requires two poles and for the disc to have considerable girth.
The second theory is much more interesting. It states that there is only a single pole at the centre of the disc and the magnetic field is radial. Currently, radial magnetic fields are are not possible with Maxwell's equations. Maxwell's equations state that the net magnetic flux is zero. The equation is
Integral(magnetic field . Change in area).
Radial magnetic fields will cause the change in area to be non zero.
However, string theory allows us to modify maxwell's equations so that the magnetic flux can be non zero. Therefore, magnetic monopoles and radial magnetic fields can exist.
This theory requires the disc to have very little thickness.