You will be using the San Juan Bay Terminal since it is just a Port stop.
The Old San Juan Cruise Port (also called the San Juan Bay terminal) is a port in the city center, allowing passengers to walk to Old San Juan attractions, whereas the Pan American Terminal is across the bay, closer to the airport, and requires a short taxi ride to reach Old San Juan. The choice of terminal depends on the cruise line and the ship's schedule, with homeport ships often using Pan American and transit ships typically docking at Old San Juan.