I would suggest searching online for articles on cruising. You can search for articles on "First time cruiser", "Do's and don'ts about cruising" etc.
Even NCL's website has articles for first time cruisers.
I also like to read about the ship and look at the floor plans to see where the restaurants, theaters etc are located. That way by the time you board the ship, you already have a fair idea on where to go on the ship.
Most of all, enjoy ... it's a vacation!!!!
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