Want to sync the calendar on your Mac with your phone or with another calendar, Here’s how it’s done. Open the Calendar app.
Here’s a look at the calendar.
Click Calendar in the upper left.
Choose Preferences from the drop-down menu.
Click the Accounts tab.
Then click the + symbol.
Select the calendar you want to add. Choose Google for an Android phone and iCloud for an iPhone.
Log in with your Gmail address and password. For iCloud, use your Apple ID and password.
Choose which functions you want to sync with your Mac. Then click Done.
Your Google calendar will now be synced with your Mac.