We flew to Miami the day before embarkation and stayed at the Marriott Biscayne Bay -- which was nice and less than 10 minutes from the port.
After breakfast, kindly included by the hotel in the "cruise package," we left for the port and arrived about 10:15am. It looked like utter chaos; there were 4 ships in port and people were coming and going like crazy. Once we figured out which door to enter, things were much smoother. There were no lines to fill out the health questionnaires, and we waited only 5 minutes before being called to the counter to check in, get our ship cards, and provide a credit card for incidentals (why can't NCL allow you to set up your account online?). Then we went upstairs and waited.
If you go over by the windows next to the ship, you can connect to the ship's WiFi and get on the iConcierge app. From there, it may allow you to book specialty restaurants and comedy shows, but it is rather slow.
Large enough for our purposes, comfortable bed, roomy (for a cruise ship) bathroom.