How to build an appointment booking modal that stores to DB and syncs with Zapier / API?

I’m looking to build an appointment booking component I can use on my Plasmic builds in a modal. It will be the first of a few components which I will store the input in a DB and sync to a portal with Zapier or an API. I’m interested to know how others might approach this?

It appears to be a good use case for custom code components. Or are there specifics bits of it that you need ideas on?