It's bold because it's stated as fact and it's thoughtless because you neglected to consider the first hydrogen atoms or elements created in labs.
Stars in the flat earth model work the same as they do in the round earth model.
I hope this satiates your sordid curiosity.
So, the sun is the same in both models, bar the 9,999,968 mile diameter discrepancy?
And the sun formed around 4.5 billion years and has been constantly fuelled since that point with a likely additional lifetime of 5 billion years beyond this point (if it's not destroyed when our galaxy collides with Andromeda in 3 billion years). To be compatible with your model, the sun must be incredibly dense to contain enough fuel even for the 4.5 billion years it has survived, without burning out and collapsing, for. Yet this incredibly dense nuclear reaction, as dense as most post supernova neutron stars, hovers by an invisible force over the Earth's surface at a height of only 9,000 feet and doesn't, somehow, rip the planet to shreds in seconds? To put this into perspective, to be that dense, and that small, it's gravity would be likely to approach 2 x 10^12 m/s/s with an escape velocity of 100,000 km/s...1/3 the speed of light and far, far above your UA that's pulling us all to Earth? So why does the Earth still exist. In your model, the Erath would have been destroyed by the Sun's gravity in mere milliseconds.