open page with "Run AJAX snippet"

I am no programmer.
I am using PHPRunner 9.8

In my project, on a _list page with images, on clicking the images, I would like to open a new webpage showing the larger images.

What I did:
on the page tab -> click actions... -> I choose my image field name (this is FN) --> I hit "Run AJAX snippet"

I use this code, to build the url in order to open the webpage,
//code
url: "http://localhost:8085/images/" + row.getFieldValue("FN");

but I do not know the right coding to effectively open the webpage with the fetched url.

Any suggestion ?