No human being on Earth has any idea what the universe is. If someone murders someone, gets away with it, then dies alone with the knowledge of the murder, at least the knowledge existed. No one now, or ever who lived on Earth has any idea at all what is going on.
There was a point in the earlier universe before any intelligence had evolved on any planet where no one even know the Universe existed. At least now we know something exists, but that's all we know. What is truly fascinating, there is a very real possibility, perhaps even a probability, that literally no entity in all of creation knows what's going on.
Even if we figure out all the laws of physics, even if there are other dimensions, multiple universes, it very well may be the case that no one understands what this phenomenon called existence is.
Gödel’s Incompleteness Theorems state:
“in any consistent formal system F within which a certain amount of arithmetic can be carried out, there are statements of the language of F which can neither be proved nor disproved in F. According to the second incompleteness theorem, such a formal system cannot prove that the system itself is consistent”
What if the system is reality, and there is no outside of the system? Everything exists within the system so there will always be a lack of knowledge for any entity ever to exist.
I find there is something almost unsettling and comforting at the same time about that idea. No matter how far we come, or how much we learn, how effectively we can manipulate matter, energy, time, at the very basis of all of it, is an unknowable mystery.