The term "how to be a captain on a cruise ship" is a noun phrase that refers to the process of becoming a captain of a cruise ship. A real-world example of this process would be an individual undergoing training, education, and accumulating experience to qualify for a captain's position on a cruise ship.
This process is important because it ensures that cruise ship captains possess the necessary skills and knowledge to operate a cruise ship safely and efficiently. The benefits of becoming a cruise ship captain include a rewarding career, the opportunity to travel the world, and the chance to lead a team of professionals.