Graviton is a hypothetical particle considered as a quanta of Gravity, if it is considered as a particle, does Gravity has momentum ?
Gravity indeed has momentum, but this is only the case insofar as we are able to define "momentum" for any field theory. Nothing about it has to do with particles. For example, there is a notion of "momentum" for the electric and magnetic fields. The same is actually true of other quantities like angular momentum too, see for example here.