A theorist friend of mine came up with an idea of a quantum interference detector..
I am trying to build it. We need about 1M for the the ground prototype and 100M to fly it. The full system is a 100G detector. linked quantum fountains..1Tm apart. It should detect gravimetric events at 10Mparsec distance... we could use a cm specialist who understands how to create a qm coupled particle fountain from a bec.

I think you will find many answers to your questions in the article "Our Expanding Universe: Age, History & Other Facts." I won't list them here but will refer you to [space.com]

We don't have enough information to speak about anything about the universe prior to about a microsecond post event 0 (the big bang has to much bagage for most people). we have some data up to particles around 10^18 ev. event zero is plank scale .. about 20 orders of magnitude higher.

With our current understanding of the early universe I doubt we are even able to ask all this in one question, never mind give it a single answer. The way I look at it, which can never be more than an easier to understand substitute for the facts, perhaps for the first period of expansion (microseconds? millions if years?) the building blocks of matter were so densely packed that they couldn't exist in any form that we see today. To touch on what's been mentioned already, maybe the start was just a pair of extremely high energy opposite particles who's sum was nothing, that each broke down into a colossal number of more familiar particles as the decrease in density allowed, maybe in several stages. Particles is no doubt too simple a word considering they constituted not just matter but the actual dimensions through which they expanded. The breaking down into familiar particles would create collisions that bound some particles and sent others in different directions than the general direction of expansion, after which the fundamental forces would eventually lead to what we see today.
I don't pretend to have much of a clue what I'm talking about but something along those lines seems to my understanding to fit with what is known or surmised. I'd be happy to be corrected though!

Some theorize that we could be inside of a black hole-to me that’s fascinating! Black holes ingesting matter and effectively becoming ‘white holes’ inside their respective event horizons/singularities. Theoretical physics is super fun for me to think about until I inevitably run into the mathematics wall!

well, so is physics. There is no definite conclusion just hypotheses.
One hypothesis is that there is never a perfect vacuum, opposite particles can appear out of nothing without requiring or adding energy in a close system. Think of digging a hole in the ground. The level ground has zero energy. Once you have a hole and a pile on dirt, the hole represents the exact opposite of the mound of dirt yet their sum is zero. Something could appear out of nothing assuming the sum of all particles is zero (protons, antiprotons, matter, antimatter, etc..). This would be the basis of Supersymmetry. (this is a start)

Lots of questions here - some misconceptions. I will only attempt to answer one question and leave others for other members. All elements other than Hydrogen (1 proton essentially) were created in stars. Low mass stars fused protons into nuclei at their cores, creating heavy elements up to iron. More massive stars produced more of those elements during their lives plus everything heavier than iron in the throes of their deaths. Those death processes help enrich space so that new stars form from richer matter. And the recycle process continues...