fancybox on indexpage – AF

Hello,

I searched the internet several times but I can’t get my Fancy Box working the way I want to on my blog (https://showme.flo-bauer.de).

I want use a fancy box on my index page as a gallery. So if you click on a picture (you can see how it works on my blog), it should load a fancy box with the picture in it without loading the article page, where the picture was attached in. So if you’re closing the box, I still want to be on the index page.
AF+ brings an plugin what does this, but only on galleries and also only on the loaded article.

There is already a blog (https://www.adailylifeproject.com/) what does exactly how I imagine it and the user also asked here for help. Sadly I can’t find any contact information to ask the author herself.
What code could I use for this? And in which file should it put it in? And would it be possible, to load a gallery behind that photo? I can’t find any stuff for this on the web..

Thank you in advance.