A shared calendar can help you quickly see when people are available for meetings or other events. Learn how to set it up.

1. In Outlook, select the calendar icon.

2. On the Home tab, choose Add Calendar -- From Address Book.

3. Add users to the shared calendar by entering their name or selecting their name from the list, and then choose OK.
You can now view your calendar and the calendars for the people you added.

4. To check your group's availability, choose the Day view.

Support article: https://support.microsoft.com/en-us/office/create-a-shared-calendar-8385667b-d758-4489-a53f-f542dd01e6ff?ui=en-us&rs=en-us&ad=us