Go to Google Console Platform.
Create New Project.
https://www.youtube.com/watch?v=WahkiQgtMuk&ab_channel=mb-techs to create credentials in google console platform.
Add the google calendar api ooptions of course on add or remove scopes.
And choose oauth client id and download the fianl json.
Add the name in the correct object line 32
Run python3 add_birthdays.py