Install Thunderbird. For calendars see Import IT calendar into Thunderbird (linux).
Install the Lightning add-on. You may also need to run {{sudo apt install xul-ext-lightning}}. Install the Exchange Calendar add-on.
The exchange server URL is: https://outlook.office365.com/EWS/Exchange.asmx
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- Add new account
- In your address book select Add Exchange contact folder
Add a calendar