WordPress multi step form Zapier webhook integration and "Thank you" page redirection

General information for the website: Need to send form data to a webhook URL and then redirect user to a thank you page
Kind of development: Customization of existing website
Num. of web pages/modules: 1 or 2
Description of every page/module: I'm using Wordpress and already have a customised working web form and just need some help with the back-end functionality.

Basically, I want to take the form data and send it to a Zapier webhook URL, then once submitted redirect a user back to a thank you page on my site.

Should be pretty simple, but is beyond my abilities.
Description of requirements/features: I'm using Wordpress and already have a customised working web form and just need some help with the back-end functionality.

Basically, I need to take the form data and send it to a Zapier webhook URL, then once submitted redirect a user back to a thank you page on my site.

Should be pretty simple, but is beyond my abilities.
Extra notes: