You have those emails forwarded to the parser, you indicate which parts you want to extract and then on later steps of your Zap you can map those into the Google Calendar date and other fields. More info on the Email Parser: https://zapier.com/help/create/email-and-text-messages/set-up-your-email-parser-account-in-zapier
The important part is having a way to automatically send those emails to the email parser, either directly from the form submission source (if they're notifications, for example) or setting something up within Gmail to have them forwarded to the Email Parser address you set up.
Thus your Zap will then begin with an Email Parser trigger.
You have those emails forwarded to the parser, you indicate which parts you want to extract and then on later steps of your Zap you can map those into the Google Calendar date and other fields. More info on the Email Parser: https://zapier.com/help/create/email-and-text-messages/set-up-your-email-parser-account-in-zapier
The important part is having a way to automatically send those emails to the email parser, either directly from the form submission source (if they're notifications, for example) or setting something up within Gmail to have them forwarded to the Email Parser address you set up.
Thus your Zap will then begin with an Email Parser trigger.