I am from the beautiful Island of Puerto Rico so if you need help please let me know

Well there are few "free trolleys" near port from our tourism departmentin San Juan, so if you are lucky you will not have to pay…
If you dock at the Carnival Destiny port is walking distance, if you dock on the AOS is better to take a taxi and yes “ El Morro” is free but remember now san Juan is “peatonal” so the taxi I believe will not get you directly to “El morro” just near to it you will have to walk anyway...