One place to start would be the Slow Travel Italian Language Lessons. Good lessons to start out with would be "Conversation Bookends," "Counting to 20" and "Caffe Talk."
You might also buy a good phrase book.
And BTW, "pronto" is also used in Italian, but with a somewhat different meaning. While pronto is usually used in Spanish to mean "quick" or "speedy," in Italian it's usually "ready" or what you say when you answer the phone.
The fact that you speak Spanish is as much a problem as an advantage. While the two languages share their Latin root, they are different enough to make them not communicating: for instance, consider that "burro" in Italian means butter, while in Spanish it means donkey. Having said this, you could be perfectly fine in itlay, especially in the most touristy areas, not knowing a single word of Italian, since many Italians (especially the younger generations) have at least some rudimentary knowledge of English, and the number of people that can speak and understand at least at some level English is much highier in the most touristed areas. Being able to speak at least some courtesies is a polite thing, obviously, so your "grazie", "prego", "per favore" and "scusi" (and a handful of greetings) are enough to just make yourself even more welcome.