An app-specific password is a one-time code generated at appleid.apple.com that lets a third-party app access your iCloud data securely. You’ll create one in the steps below and paste it into Cal ID, so your real Apple ID password is never shared.
1
Open the Apple Calendar app details
Go to Cal ID’s App store and click on Details under the Apple Calendar card.
2
Install and open the setup page
Click on the Install button or, if you already have an Apple Calendar connection, click on the Install button. In the Apple Calendar connection setup page, click on the link and sign in to your Apple ID.
3
Open App-specific passwords
Once signed in and on the 
https://appleid.apple.com/account/manage page, click on App-specific passwords.4
Add a new app-specific password
Now, click on the plus sign to add a new App-specific password to your account.
5
Name and copy the password
Next, provide a name for your new App-specific password. You should now have a new app-specific password showing on the screen. Simply copy this password.
6
Enter your credentials in Cal ID and save
Now enter your Apple ID and the newly generated app-specific password (you copied this in the previous step) in the Cal ID Apple Calendar Setup page. Finally, click on Save. You should now be redirected to the 
https://cal.id/apps/installed/calendar page showing your recently added Apple Calendar.That’s it. Your Apple Calendar is now connected to your Cal ID account.
Next steps
Connect Google Calendar
Review the permissions Cal ID needs to sync Google Calendar.
Add Zoom to events
Set Zoom as the meeting location for your event types.