I live in Montreal, not Quebec city (3 hours away).
However, I can make some basic recommendations.
Quebec city is a beautiful city, with alot of interesting architecture, and of course, food.
I recommend staying in the old part of the city (cobblestone streets, French cafès & restaurants, lots of character). You can basically walk to everything of interest from this area (maybe not the cruise port).
The grandest hotel, with best location and views is the Fairmount Chateau Frontenac (however, could be expensive, depends on your budget). You can get very charming smaller hotels, less expensive, in the same area. For ground transportation, I recommend taxis/uber (unless the hotel you choose has airport transfer and/or cruise transport.) Happy to help with any other questions.