A ship's captain is in charge of the ship. The navigator plots the ship's course. The engineer looks after the engines that drive the ship along. The helmsman is at the wheel and follows direction from the officers as to the course to steer. Then there are other members of the crew.
A waggoner is a person who drives or rides on a wagon.
That fellow is known as the "ship's carpenter" or in a dockyard as the "Shipwright"
The captain
It depends on where the ship is. On the open sea, the captain or any crewman he assigns may drive the ship. While in a harbor, or a channel such as the Inter Coastal Waterway (ICW) along the east coast of the US, a pilot or harbor pilot steers the ship.In many Navies the person who drives the ship is known as a Helmsman.
The term is, "Passengers embark"
A wagon is a four-wheeled cart for hauling loads, or a freight car on a railway.
A person that drives a passenger actually drives the car for the owner. This special essential person is called a Chauffeur.
A "Pilot" is a person who drives a plane.
Yoda drives the Republic Attack Gunship.
The term pilot was first used as a naval term in the early 1500's, meaning the person who steers the ship, which is not (necessarily) the same person as the captain. In the mid 1800's the term pilot also included a person who steers a balloon, and in the early 1900's its meaning was expanded to include a person who flies an airplane.
A cager is a basketball player, or a person who drives an automobile for commuting, a term used pejoratively by cyclists to refer to non-cyclists.
The term you are looking for is stowaway.