Who invented the first ship in the world?

The only viable answer would be "The first shipbuilder" and we don't know who he or she was.

Water transportation started in the stone-age when the people built primitive boats to help them navigate rivers and lakes while fishing and so on.

The oldest known boat (a canoe), carbon-dating indicates that it is from the Mesolithic era between 8040 BCE to 7510 BCE.

The Khufu ship is the largest preserved ancient ship and is about 143 ft long and 19.5 ft wide. Khufu ship is currently on display in Giza-Solar boat Museum, and it is believed to have belonged to the second Pharaoh Khufu of the old Egyptian kingdom. The vessel was sealed in the Pyramid complex in Giza around 2,500 BC, and just like most of the buried Egyptian ships, the Khufu ship was to be used in the afterlife.