Italy like most of the world have numerous broadband providers, one thing Italy has that many countries don’t have though is a wireless/mobile broadband that is reliable, covers most of the country and does not need a landline.
Linkem is the main provider of this type of internet.
You can sign up online or in any phone shop in Italy, its quick and simple, and it takes a couple of days for the equipment to be installed, you may need an antenna installed. You will be able to see this when you sign up.
https://www.linkem.com/ If you use this customer code CBD2529 you get a month free.
The site is in Italian you might need to use Google translate, but its relatively simple. You will then get a phone call from your local installer, I just didn’t answer, searched the telephone number on google, then emailed them about it, was easier than me trying to understand what they was saying on the phone.
English (UK) 
Italiano