Hi @Jade Henderson
According to the Microsoft 365 International Availability, Microsoft Teams is available in Greece along with many other countries and regions. You should be able to access the call as long as you have an internet connection and a compatible device.
However, you may want to check if there are any dial-in phone numbers available in Greece in case you need to use a phone to join the meeting. You can do this by going to Teams admin center > Voice > Phone Numbers, clicking Add , and then clicking New Service Numbers. Use the lists for Country/Region, State/Region, and City to filter your search. If you are looking for toll free service numbers, select toll free from the State/Region list.
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