Origin of Universe

In our childhood there was always a question in our mind that who came first, the hen or the egg? similarly ,there was one more questions which makes our mind blow that how and when did our universe came and when did we know about it? And how this universe works and many more such questions. " Two things are infinite: the universe and human stupidity; and I'm not sure about the universe”  said Albert Einstein.  Our universe is a full of an independent Ocean like our mind i.e there is no any boundary of the universe. So ,Let's go for a dive in this infinite ocean.   A Universe is everything from the tiniest particles to the largest galaxies, to the very existence of space - time and life , the  spatial size of the entire universe is unknown, it is possible to measure the size of the observable universe, which is currently estimated to be 93 billion light-years in diameter and According to research, the universe is approximately 13.8 billion years old but  how did it all b