1/ Alright, I will now respond how "elements come from nowhere." This explanation will be shortened and will leave out some nuanced information, but the content will be there and will address the main points.
First, we need to agree on some things and by agree, I mean these are indisputable facts:
Stars move in space.
Other Galaxies exist in space.
There are other galaxies in the universe other than the milky way galaxy. The closest galaxy being the Andromeda Galaxy (confirmed by the Hubble Telescope.) We also see that these galaxies are moving away from us (and each other, much like how raisins spread apart when baking raisin bread. Space between all entities is increasing in every direction. We can tell how fast they're moving by measuring the red shift of the light that is coming off of those galaxies. When you plot graphically their distance and the speed at which they're moving, you come up with a straight line on a graph, they are proportionate to each other. The slope of this line y(1)-y(2)/x(2)-x(1) the slope of this line is called "Hubble's constant." It is written as H(subscript 0). We can express the aforementioned proportionality with an equation which is velocity is equal to Hubble's Constant times Distance. Or, v=H(sub0)*D. That is Hubble's Law. Like in Algebra, you can take the equation and shift it around to verify that the equation and solution are correct. Such as this: 1/Hsub0 = D/V. (H=Hubble's Constant, D=Distance, V=Velocity.)
In Physics, D/V is equal to Time. So, if we solve for D/V, we get 1/Hsub0 = t. Not just the time as a specified measurement in this instance, but the entire concept of Time itself given the nature of the expanding universe and the movement of the galaxies. When you calculate this number, you get roughly 14 billion years (rounded.) It is true, there is some debate about how much time *exactly* has passed, but they are arguing over decimal places over this number, not whole integers; they've narrowed their answers within one billion years. On this, all involved in the academic debate agree. Hubble's Constant is still being defined. As more data pours in, we get closer and closer to the accurate number. Hell, we can even measure the energy of the universe, but I haven't listened or studied about that topic... yet.
The Big Bang actually (upon checking notes) started with 0 elements. Matter had not cooled down enough for elements to form (yet). Once it did, it formed the most simple elements: Hydrogen and Helium