Multi-Category Dropdown Search

Hi Webflow community!

I am working on a client project that is a CMS based site, and I am looking to create a “multi category” search function … attached is my unpublished site - its not completely built out yet, as I am still working on how to set it up exactly ( - any suggestions on how to set this up or resources to look at?

Here is my site Read-Only: LINK
(how to share your site Read-Only link)