Hello Nora,
Good day! Thank you for posting to the Microsoft Community. We'll be happy to help!
Based on your description, I understand that you are having a query about having multiple calendars in Teams.
Indeed, this is now possible with a new feature "New calendar in Teams", please note that this feature is still in public preview.
Reference: Get started with the new calendar in Microsoft Teams - Microsoft Support
To enable the new calendar, please go to your Teams calendar > and enable new calendar toggle (Top right conner):
Please let me know if the above information helps, and if you have any further clarifications, feel free to respond to this thread.
Thank you for your understanding and I look forward to hearing from you.