Suggest you do some research on the movement of cargo/goods by ship. Especially investigate "transportation logistics" Also, if your goal is Navy active duty, strongly suggest either USNA or Navy ROTC routes. It's true that KP grants navy reserve commissions, but that's not its primary mission. Good luck whatever you decide.
Marine transportation includes the fundamentals of nautical science, communications, technology, and such along with integrated navigation courses, where you will build technical competency with your nav equipment and using it to aid you in safe navigation, also courses about ship stability, cargo ops, etc. Everything a mate needs to know, in addition to the principles of business and if you opt for Logistics, you will learn maritime logistics and do a capstone project. Interesting major, not very practical outside of the shipboard world, in terms of directly transferable skills. If you are keen on acquiring skills that would make civilian employment ashore a breeze, go Marine Engineering Systems/Shipyard.
Active Duty in the Navy is possible and even likely if you're the right type of guy, but not guaranteed. KP is the second largest single commissioning source for Naval Officers behind USNA, so we do commission a decent number in the Navy, last year was around 30. SWOs, 2 Nukes, Pilots, NFO, etc. Definitely a possibility, but you must be prepared to accept the fact that an Active Duty position in the Navy is not guaranteed.