It is true that Noah's Ark was the first boat mentioned in the Bible, but most scientists and historians do not believe that this means it was the first boat ever built.
There is, of course, no way of knowing when the first boat was ever built. We can say what the oldest boat ever found is, but that doesn't mean it was the first boat ever built. Boats were being built before people started writing things down, so we have no idea who actually made the first boat.
This idea is captured in this quote:
"The basic problem is that all boats are made out of organic materials that just don't preserve in the archaeological record," said Professor Knut Fladmark, of Simon Fraser University in Canada.
Professor Fladmark believes humans were building boats 40,000-50,000 years ago and cites evidence that Australia was colonised by this time despite the fact there was no land bridge connecting it to South East Asia.
The oldest boat that's ever been found is from about 7,000 years ago. It was found in Kuwait. But this was a serious, ocean-going boat. So no one believes it was the first one ever made.
So the short answer is that no one will ever know when or where the first boat was made.
I know that the Ark was the first mentioned in the bible. However there are many other references to fishing in the bible too. There was definitely someone else building boats.