Actually you can view multiple calendars at the same time. If you edit any item in Outlook, those changes will NOT be reflected/saved. Not seeing the calendar that you want to use? In the navigation pane, select the calendar under which the new calendar will be saved. At Ignite 2019, Microsoft announced an all-new Outlook for Mac experience with redesigned UI, improved performance and several new features.
As you can see, there are two different methods to sync an iCloud calendar with Outlook. In the section named “Open these additional mailboxes: “, click the '+' button. In Calendar view, … repeat step above to see that it has synced Outlook for Mac always displays calendars in overlay mode when it shows four or more at a time. to set up and manage your email and calendars using Outlook for Mac in Microsoft 365 (formerly Office 365).
