Ashore Shore Excursions are available on cruises. Information about the excursions will be in your cabin. Read the material carefully because it will tell you where and when to sing up.
Most ships offer an orientation and it is highly recommended that one family member attends.
You can also choose to do your own thing at the various ports. Taxi drivers are usually available right at the port and they will take you where you want to go. Have them price the trip for you up front, that way there will be no misunderstanding. The cruise line gives you a Boarding Pass when you check in at the pier. You must take this with you when you disembark at the ports.