Using New Outlook on Windows for personal email, calendar, and contact management
Hi , classic Outlook’s standard Gmail setup syncs email, but not Google Calendar.
You can still view it: in Google Calendar, open Settings >> select your calendar >> Integrate calendar, then copy the “Secret address in iCal format.” Keep this link private.
In classic Outlook, go to Calendar >> Home >> Open Calendar >> From Internet and paste the link.
This is read-only, so you’ll need Google Calendar or new Outlook to create or edit events.
https://support.microsoft.com/en-us/outlook/calendar/see-your-google-calendar-in-outlook