Question: Is Big Bang Theory the only one to explain the creation of the Universe?

I have read about Big-Bang Theory explaining the creation of Universe. Is there no other theory to explain the creation of Universe?

If there is another theory please explain it to me.

I will appreciate your help

Answer: 
The big bang **model**$^{1}$ is an attempt to explain a host of observations that tell us how the universe evolved from its first fraction of a second onwards.

It started off by being grounded in fundamental and rather well understood physics (General Relativity, particle physics and nuclear physics at *relatively* low energies). The model itself has evolved and become more complex in response to new, more detailed observations and has had to add new, poorly understood phenomenological features (incorporating dark energy and dark matter, sometimes referred to as the $\Lambda$CDM model) to remain consistent with those observations.

Whilst the big bang *model* is a means to describe the past, present and future development of the universe, it does not have the fundamental status of a theory. Notably, it **does not** explain the creation or origin of the universe.

None of this really answers the question. There are lots of ideas and speculations about how the universe was created, but none of them can claim to be a "theory".

$^1$ Note there is a difference between a [theory](https://en.wikipedia.org/wiki/Scientific_theory) and a [model](https://en.wikipedia.org/wiki/Scientific_modelling). The latter is set up to explain a specific set of observations or a specific scenario; whereas the former is much broader and fundamental. See also [What is the difference between a "model" and a "theory"?](https://physics.stackexchange.com/questions/187967/what-is-the-difference-between-a-model-and-a-theory)
I am no expert in cosmology, but I do know about shockwaves and the Big Bang is just a shockwave in a compressible medium. It is fundamental that shockwaves lose information, and so observations made after a shock has passed allow only a limited reconstruction of what went before. There are apparently solutions to the Einstein equations that describe an explosion inside a pre-existing medium, and the post-shock properties are said to be indistinguishable from those of a shock that propagates into nothingness. See Smoller, J. and Temple, B., 2004. Cosmology, black holes and shock waves beyond the Hubble length. Methods and Applications of Analysis, 11(1), pp.077-132. I believe that this is not taken seriously by cosmologists but I dont know why.