I've been getting some of my team members set up with ClickUp this week, and we've found it confusing to set up the 2-way sync w Google calendar.
It seems to work best if the user first goes into their Google calendar and creates a new calendar named something like "ClickUp Tasks ([My Office Name])" where "My Office Name" is something like the Company's name. This helps make it clear when you open ClickUp, which calendar you're sync-ing with.
Then the use can go over to ClickUp and complete the sync, choosing the new "My Office Name" Google calendar.
It would be helpful if the ClickUp sync wizard included some instructions along these lines. This set-up has the benefit of making ClickUp tasks a appear on Google calendar in a different color, and giving the Google-calendar user the option of turning them off or on.
Thanks for considering this addition!