train from Lake Orta, Italy to Florence, Italy

The problem that you are probably having is that "Lake Orta" is a lake, not a town, and railway stations are in towns. You also have to spell Florence the Italian way, "Firenze". And the lake is really called "Lago di Orta".
According to my map there is a railway line along the east side of the lake. "Pettenasco" in the middle has a station.
I looked it up and found 4 possible trains per day, taking about 4 hours for the trip. For example:

Depart Pettenasco 08:55, arrive Novara 09:40
Depart Novara 10:05, arrive Milano Centrale 10:46
Depart Milano Centrale 11:15, arrive Firenze S.M.N. 12:55

I doubt a Travel Agent in a foreign country could help. You just need to know how to look it up (online map, find correct station name, then railway company website).

In Europe, the question "is there a train from A to B" is really "what are the names of the stations nearest to a A, and to B".

Chris, thanks so much for the information ! I appreciate your help. I will look at it again from this perspective !

The "Orta-Miasino" station is about an mile from Orta. There are trains from this station to Florence, but none of them are direct; The trip takes about 4 hours you will need to switch trains in Novara and Milan. See the Italian Rail website, Trenitalia for schedules and ticket prices: www.trenitalia.com (click on the British flag in the upper right corner for English).

As Chris mentioned, when using this site, you need to enter the Italian names, such as "Firenze" for Florence.

Your tour guide can assist you with transportation from the hotel to this station or the Novara station by cab or shuttle, possibly sharing with other tour members who will also be taking a train. You can buy the train tickets at any station beforehand, such as in Levanto.

The Trenitalia site has a pull-down menu for station/city names, get the first few letters right and you can choose the station. Firenze has multiple stations, you want Firenze Santa Maria Novella.