How to create a contact in Campaigns when a user signs up on my Firebase app

Presently, I use a Firebase extension to sync users email addresses with Mailchimp. This happens when they sign up to my app. I want to replace mailchimp with Zoho Campaigns but Firebase does not have an integration with Zoho so I have been told to use Zapier.

Can anyone help me do this?

As soon as a user signs up with my mobile app, I want to create a contact in Zoho Campaign List.

Thank you