According to the standard big bang model of cosmology, time began together with the universe in a singularity approximately 14 billion years ago.

What existed before the beginning of time?

The initial singularity is a singularity predicted by some models of the Big Bang theory to have existed before the Big Bang and thought to have contained all the energy and spacetime of the Universe.

Does time have to have a beginning?

If time is like a torus, it may be cyclical in nature, rather than having always existed or coming into existence a finite amount of time ago. ... But in our quest for the beginning, we know already that time couldn't have started with the Big Bang. In fact, it might not have had a beginning at all.