CMS and how to build a product site

Hi, working on a project for a client, and we started out with some pages, and now sadly reached the 100 cap.

Going to try out the CMS, but I have a hard time figuring out how to move forward. We got a design on the product pages with a Grid. I have set up different CMS pages, but there will be a different amount of images for each product, and up to now, I have made a new page, places the images (yes, I know, a background image is not the best way to do that but I an open for getting some tips on using images on the same way), and then removed the grid boxes that were left. But not sure how to do this with a CMS system so that the page doesn’t have a lot of Grid boxes not in use.

So to be clear: I want to make these type of pages: - with a different amount of images on each page - while using CMS.

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Thanks a lot guys!!

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