That question is implicitly suggesting that the universe was created. If that turns out not to be the case, then not even an omniscient being could answer it correctly. It would be equivalent to asking “describe the true process by which the Earth came to be flat.”

Of course, humanity does not understand everything about the universe. For instance, there is still the huge open problem of unifying general relativity with quantum mechanics, which is essential to understanding the very early universe (the standard model starts to lose accuracy prior to 10^(-32) seconds after the Big Bang [0]).

But that does not mean humanity will never understand such things.

And in case you are thinking “we’ll never know for sure; we’ll only have theories”:

I contend that all knowledge is inherently probabilistic. To claim to know something with absolute, 100% certainty is a fallacy [1]. After studying math my whole life, I am pretty confident that multiplication of integers is commutative. Is it possible that I have misunderstood numbers for my whole life, or that I am hallucinating right now, or that all of humanity has made the same mistake throughout all of history without realizing it? Yes. Just very, very improbable.

But that does not take away from the notion of understanding. One can understand an idea, while simultaneously recognizing that there is a small chance their understanding is flawed.

[0] https://en.m.wikipedia.org/wiki/Inflationary_epoch

[1] The notions of “probability 1” and “certain” are actually distinct; for instance, if you flipped a coin for every integer, the probability that at least one would turn up heads is 1, even though it is possible for them to all land tails. That being said, the existence of real-life phenomena (cosmic rays, parasites, etc.) that could affect our minds at any given time ensures that no claims of knowledge can ever have probability exactly 1.