If you do not want to rent a car....you could stay in one of the hotels in the Westshore area.
Most of those hotels pick you up from the airport for free and have complimentary shuttles within 3 miles.
There is a mall you can walk to etc.
They do not take you to the port for free.
That will cost you about $22 dollars one way.
We stayed at the Embassey Suites - Westshore and it was fine.