Nested Collection Current Item


I want to create a gallery of 5 images in a row on the right half of the screen and when clicking on a single image an information div should pop up on the left side with the clicked collection item. I somehow struggle to realize this.
I created a nested collection list with 1 list containing images and the other containing the other information. Overall it’s working out, but I am struggling to limit the information in the div to the current nested item. Can you help me how to do it please?

Currently when you click on the image you will either see all according desriptions or I limit it, without achieving my initial goal.

If I do it with a single list i struggle displaying all items while only displaying one information div.

Thanks in advance.

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