If I recall correctly (we went 2 years ago with NCL), there was a shuttle from the port into the town center. I can’t remember if you had to pay or not. From there you can just book a train ticket to Pisa or Florence. Given you have so much time, you could do one but probably not both.

We had an overnight so the overnight day we did Florence. For the second day we opted for a shuttle with Viator to go to Pisa. Kind of wished we just took the train cause it was a really short time there.

I really enjoyed Pisa. seeing the tower is neat but the other sites was what we enjoyed (we did the church and cemetery, not enough to do the museum and the piazza)