I plan far in advance.
We like to do a cruise in conjunction with a lengthy land trip. We are retired and can take all the time we want.
First, we decide on a cruise. We have done most of the cruises (15 on NCL and Celebrity) that were on our bucket list, as well as land tours combined with river cruises (4, three on Vantage and one on AMA).
Second, booking the cruise a year and a half out, we get to pick our cabin. Nest, I plan the land trip. The hardest part is picking where to go, since options are many. We have been to 70 countries, and lived overseas for several years, but there are still places on our bucket list.
Third, once we pick the places we plan to visit. after having done some research on things to do there, picking a hotel or B2B is next. Usually do this several months out, but not a year out. After picking a hotel, if there are tours to book that is usually done 4-6 months out. Also, if a car rental is involved, that is booked.
Fourth, air is usually booked 9-11 months out. If using miles, i have found that it is better to book with miles early.
Restaurants, we rarely book in advance.
If you are 38 days from departure, you are a late planning from my perspective, however, your plans are rather limited in scope. When planning such a trip, you must choose rail or car rental.
In Italy, I prefer rail to car rental, but not sure how well your rail connections will work. If rail is your choice, I suggest research your trip and book inadvance, unless you plan to take local short haul trains. If car rental, plan your route and try to plan were you will park, sleep, tour, etc.