Using CMS for more product info within modal

Hey everyone!
I’m pretty new to Webflow, and definitely new to CMS, but am loving it all so far!

So I’m in the process of making a page for a jewelry store, and am focusing on the product galleries. I have set up a pop-up modal that shows the original image from the gallery, as well as other views of the pieces of jewelry.
I’ve set up a couple collections (one with just stock images, another with a couple actual photos of jewelry), and tied them in to my gallery and modal.

What I would like is for the user to be able to click on the image from the gallery, and have a modal with more views of that same piece, that can be clicked on and seen larger (if you look at my site preview, and see how the modal is set up, you’ll see what I mean; I want the images along the bottom to replace the larger one at the top).

My question is how do I do this with CMS? I just want one image of each piece to show up in the main gallery, with more images in the modal.

The other goal is on our end. I’d like to be able to just use the editor to add to the collection list(s) so it’s easy to add images to the galleries (I trust my coworker’s web-building ability about as far as I can throw them :grin: )

I feel like this has to be possible, but I’m at a loss as to where to start to make it all work.

Here’s my read-only link: https://preview.webflow.com/preview/website-88a3d1?utm_source=website-88a3d1&preview=1def0a8281856545ed5c07e3828e13e0

and my published site: https://website-88a3d1.webflow.io/gallery

Thanks in advance!
Scott