I love swimming. I have been holding my breath underwater since weeks within my birth.
Really!  Is it natural for an infant to be able to hold their breath under water?
Yes. it is an evolutionary response to not only hold our breath, but to undertake rudimentary locomotive swimming withing weeks of birth.
That is amazing!  I imagine it must be harder to learn the older you get then, right?
I am not sure, but swimming is a very low-impact activity.