Hi Tracy, We have elevated the calendar area in the new experience to a new page and added the capability to add this area to your Main Menu in the top navigation. Currently, the default areas or icons in the Main Menu are associated with the same settings from your Layout Template in Workfront Classic. You can add new areas (Calendars, Dashboards, Resouring) to your Main Menu by updating your layout template in the new experience. This should give you access to the Calendars area, which should include your shared calendars.
Soon we will be updating this user experience to include all new areas by default in the Main Menu. Josh Boston Workfront