iCloud: Create a calendar
iCloud Calendar comes with two already-created calendars: Home and Work. You can add events to them to keep track of tasks you need to accomplish. You can also rename or delete these calendars, although you must leave at least one calendar in the list.
Choose New Calendar from the Action pop-up menu below the sidebar.
Type a name for the calendar, then press Return or Enter.
When you create a new calendar, it’s selected, so you can immediately begin adding events to it.