Creating a Filterable Menu with Cover Images

Hi all,

I've tried everything to figure this out with no luck. Any help or guidance you could give would be so incredibly appreciated. I'm creating a site that will be a resource/database for parents and educators, with a collection of PDFs that I/my nonprofit has created. I would like users of my site to be able to go to a section of my site, say, "Art Projects," and be able to see cover images and titles. I can currently manage this with using image blocks and linking to a file.

HOWEVER, what I really want to do is to create a filterable menu for these, so if a teacher had, say, cotton balls, they could click that along the side and get every project that had this. Or filter it further by finding Halloween projects that use cotton balls. 

I've attached an image of an educational site that has something similar.

Does anyone know where I can go to find the code to do something like this?

I would look into the Universal Filter by @michaeleparkour. You should be able to achieve what you want using either a gallery page or summary block with this plugin.

https://www.squarewebsites.org/products/universal-filter