how do i make phone calls in Italy

There are many possibilities depending o what equipment you have, what US carrier you have, and what volume you expect to use it. Only calls? Texting? Data? There is a lot of info here to help you https://www.ricksteves.com/travel-tips/phones-tech.

We use a SIM card for local calls on one phone, and get an international plan for the other phone.

Do you live in the US? If so, install the Google Voice app so you can make free voice calls back to the US, even to landlines (e.g. your airline). You can text people on US mobile phones too - Google gives you a new phone number you'll need to use, so give your new Google number to people who might be expecting to hear from you and not recognize the new number. Google Voice works on WiFi or with a SIM card's mobile data. Set it up before you leave home and try it out.

If you don't live in the US, you may have other options e.g. Skype (a few cents a minute to call phones intentionally). Could be your mobile phone service offers a decent international roaming option that lets you make calls.

If you don't have a good international roaming option, a SIM card will be handy to making the best use of your phone in Italy in general, though. You can buy a SIM card when you get to Italy and use it for local calls and for calling home too perhaps if the other options don't work but also to use a mapping app (VERY handy even for walking around!) . WhatsApp is popular in Europe - you can probably use it locally too (with a SIM card or on WiFi).

One question is what phone and service do you have. Most (but not all!) US phone plans will work in Italy - just call as normal. However the cost of this varies dramatically, which is why knowing your exact plan is essential. For example, my teenager has google fi and it’s exactly the same monthly fee anywhere, so no international extra cost. I have AT T and pay the ridiculous $10/day to use my phone as normal. I don’t want to mess with SIM cards and I need the phone for data, so once I pay the $10 I can call as well so I don’t need additional apps.

That said, a lot of Europeans use WhatsApp so setting that up might be needed if you plan to call local people. Businesses usually have a regular phone number, but I have seen some small ones that only use WhatsApp.

If you have access to internet, you can use WhatsApp, or Facetime, etc. If you want to make phone calls then you should buy a sim card in Italy to makes calls in italy...or get an international plan that lets you call outside of the EU.

I bought my first sim card to use on our trip, and it didn't work the way I thought. I bought the card in Munich at the airport to use in Sicily, I paid for 9G of internet, never got that to work. I was able to make phone calls and that was handy a few times on our self guided bike tour to get in touch in the middle of no where with the tour company.

I did feel stranded not being able to access the internet, not sure if that was my error, or the German card didn't work in Italy like they said it would.

Paid Euro 40 for 250 min of cellular and 9G, I don't think I got my money's worth. If I'd just paid the $10 a day when I had to use the phone, I think it would have been the same cost, or a bit less in the end.

my teenager has google fi and it’s exactly the same monthly fee anywhere, so no international extra cost.

We have Fi and so this isn't exactly correct. For data you're right, the cost is $10/GB no matter whether you are in the US or a European country. Texts are also free using either wifi or cell. However for phone calls the cost depends on whether you are using a cell service or wifi. For wifi (such as when you are connected to the wifi at your hotel or a cafe) calls back to the US are free, but if you're using a cell connection its 20 cents/minute. If calling within Europe then even on wifi there will be a charge. See https://support.google.com/fi/answer/6157794?hl=en#zippy=%2Crates-for-texts%2Crates-for-international-calls You can ensure you are using wifi by turning the cell connectivity off, knowing that if there is some emergency you can enable it and pay for the call.