How do I use my Apple Card to pay for a cruise?

It would work like a regular credit card. If you are not using a terminal that takes Apple Pay, then you would need to get the card information from the Wallet app and provide that like you would certain online purchases. If you have the physical card, you can swipe it in a normal terminal.

The issue of using the Apple Card like a regular card and swiping, using chip or entering card numbers is you lose ½ your Daily Cash Back. You earn 1% by swiping the card, inserting chip or entering card numbers. You earn 2% if you use Apple Pay, a safer and more secure way of making purchases.

These support articles explain in detail how to use Apple Pay and receive a greater benefit for using your Apple Card.

Apple Card - Features - Apple

Make purchases using Apple Pay - Apple Support

Another great feature of Apple Card is no foreign transaction fees. Enjoy your cruise!