@Margaret Menner Thanks for posting in our Q&A. For this issue, it is not related to windows 365. It is more related to Microsoft license.
Based on my research, Microsoft 365 Business Basic supports online meetings and video calls for up to 300 people with Microsoft Teams, but Microsoft 365 Family doesn't clarify this part.
And I find a article showing the Difference Between the Microsoft 365 Business and Microsoft 365 Family.
https://csolutionsit.com/microsoft365-business-family/
Note: Non-Microsoft link, just for the reference.
Or it is suggested to try to contact Microsoft 365 sales to get more accurate help:
https://www.microsoft.com/en-us/microsoft-365/business/sales-support
Hope it will help.
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