How was big bang created with an example?

Answer 1

We don't know. More specifically, no one knows; it may not be possible to know.

Example: the Big Bang. There has, so far as we know, been only the one, so we can't give you another example.

Answer 2

The Big Bang theory states that the universe began as a singularity, a point of infinite density and temperature, about 13.8 billion years ago. This singularity rapidly expanded, creating space, time, and all the matter in the universe. An example often used to explain this is imagining the universe as an inflating balloon, with galaxies moving away from each other as the balloon expands.