train to Florence

lourdes,

Could you elaborate on your plans? Are you planning to travel back and forth to Florence every day for three days?

No, you do not need to buy a Pass, especially as those don't include the compulsory seat reservations. You'd have to buy those separately.

You can use either the Freccia or Italo high speed trains from Roma Termini to Firenze S.M. Novella. The trains travel at up to 300 km/h and the trip is about 90 minutes in each direction. The two rail networks are separate so the tickets are not interchangeable from one to the other.

Note that the tickets for these trains have compulsory seat reservations which are specific to train, date and departure time so you must take the train listed on the ticket or you'll be subject to hefty fines. As this is your first time in Rome, also note that tickets for Regionale trains, buses and metro must be validated (time & date stamp) prior to boarding on the day of travel, or again hefty fines.

You may wish to pack along a copy of the RS Rome or RS Italy guidebooks as there's an enormous amount of information in the books that will help your trip go smoothly.

I am planning on staying in Rome and travel to Florence the second day and the third day to Milan and the fourth day to Naples.
tha is why I was wondering if buying a pass will be better

Passes are worth only for commuters that live in Rome and work in Florence, 1.40 hours away by fast train. I know several of them. If you are not traveling every day on the same itinerary for a long period do not consider passes.

I am planning on staying in Rome and travel to Florence the second day
and the third day to Milan and the fourth day to Naples.

lourdes, Milan is much too far away for a day trip. You'd spend 6 hours of your day sitting on a train: 3 hours each way. Besides, assuming your one day in Rome is only a partial (arrival day?), you are left with VERY little time to explore a city with a great deal to see if you spend 3 of your 4 days on day trips. Or are you staying in Rome longer than 4 days?

Had the same though initially, but then decided the OP probably isn't traveling on 4 consecutive days. I suspect the OP's first language isn't English and something is getting lost in translation. At least I hope that's the case or agree they'll spend their vacation riding trains.

I too was nervous the first time I booked train travel but it was easy and enjoyable. I agree that it is best to buy individual tickets, not a pass, and that a trip to Milan is too long for your short stay. Go to the website for Trenitalia to buy train tickets. You will see all the trains running to your destination for that day. Any class - standard, premium, or business are ok. Each city may have mutiple staions so know where you want to go, usually best to go to main train staion as there are more trains going that way. Firenze SM Novella in Florence, Roma Termini in Rome, Napoli Centrale in Naples.
One caution is that once you get to your train station, know your train # (should be on the ticket). Trains aren't like plane travel where you search by destination. Your train to Florence will probably travel on to other cities. There are big boards in each station which will show the train #, departure time, and maybe 10-15 minutes prior to departure which track it leaves from. Your ticket will show which car you need to get on what seats you have. Each car has some luggage racks.

Thank you everyone for the good response
I will be in Italy for 10 days and want to do day trips 3 days that leaves me 5 days to explore Rome.
Thank you again
Lourdes

IF you do these three day trips (and I'm also not a big fan of the long daytrip to Milan), then full/base fare roundtrip tickets bought in the station will cost roughly $100 for Florence, $200 for Milan, and $100 for Naples, total $400 in Standard (2nd) class. Costs for those are usually lower if dates and times are secured in advance.

For comparison, a Eurail Italy pass for 3 days of travel within a month costs $143 plus 6 seat reservations for $72, totals $215. The fact that you're traveling roundtrip on these segments means that you'd get more value out of a pass than most typical tourist itineraries. But if you choose a closer side trip instead of Milan, that would be a lesser ticket value.

I will be in Italy for 10 days and want to do day trips 3 days that leaves me 5 days to explore Rome.

You can do a day-trips to Florence and Naples from Rome, doable but not enjoyable; a day-trip to Milan from Rome is not realistic. Milan is over 6+ hours away, one-way. You would spend a total of 12+ hours traveling by train, in order to spend maybe 1-2 hours in Milan, you'd be wasting an entire day riding a train.

Assuming you're flying-in/out of Rome, and you're not locked-in to your hotel, you'd be better off doing the following:
arrival
4nts Rome
3nts FLorence
2nts Naples
departure

Lourdes, I'm not sure when you're going but I've learned that you should book as far in advance as you can. I waited till about two weeks out and some times were sold out on the trenitalia site. I was however able to find roughly the same ticket on the italotreno.it site. I've booked through both sites for my upcoming trip and both sites sent a conformation email with a booking code. All I need to do when I get to the train station is board and show an attendant my code and I'll be good to go. One other note about waiting to book is that the price goes up the closer it is to the travel date. Good luck.

Milan is over 6+ hours away, one-way

Milan is 2:55 or 3:20 hours away, one way. Depending on the departure time.
Firenze is 1 hour and half away, one way, quite doable as a day trip.

For comparison, a Eurail Italy pass for 3 days of travel within a month costs $143 plus 6 seat reservations for $72, totals $215.

A non refundable and non changeable Trenitalia SuperEconomy ticket from Rome to Milan costs 52 $ one way. On the other hand Italotreno, the private competing company that runs only high speed trains, is cheaper: 33 €, one way, from Rome to Milan.
Trenitalia would be more expensive than a day of travel using the pass, whereas Italotreno would be cheaper.

I am nervouse

There are many youtube videos showing the stations of Rome, Florence and Milan. You could watch a couple of them to lighten up a little.

Not sure that Trenitalia would be more expensive than a pass day. Often they give you a discount of you are doing a return trip on the same day.