Google Calendar API With Corvid. Calender event in Customer'c calendar

Hi,
I wanted to create an event in my Customer’s calendar. When I browsed in the wix forum I found a link for that.
In that I am able to create event only for my gmail calendar. I wanted to create event in my Customer’s calendar.
In that link they mentioned to save the tokens along with the email of the member and use their token and calendar id when making a call. How to get the token from the Customer and their id.
Attached link below

I think it’s easier for you to create an event file and make the user click a button to download it or just go.to() the google calendar site and have the user add it to their calendar

Have you found a good solution? I want to achieve the same function as you, but the link above is invalid