Loading images but not preloading them

I rebuilt static pages and cleared all caches each time testing.

I was familiar with that article from past attempts to accomplish per page preloading of images. This is confusing to me. I am wanting to load images with priority on a page by page basis (to shorten time for largest contentful paint). It seems that preloading is technically something else, like loading in advance of future navigation or user input. So i am completely confused. I can preload images using integration tab in divi theme, but this loads on pages where the image is not needed as well. I was thinking that this is what this plugin made possible. But not sure, cant tell if its working because i am not sure what it is supposed to do. The article mentions preloading after the page has loaded, which to me seems like the point of the plugin is something other than what i was expecting. Would like to understand it better.