How can I make my gallery buttons link up automatically to new posts/old posts?

https://pier36nyc.com/events/

I have 60 posts in total and I have 60 images in my gallery.
I want to be able to figure out how to have these links (when you hover above the image, there will be a popup that displays text and button) link up to the most recent post.

To be exact, how do I make the first pic on the gallery link to the most recent post on wordpress? Is there such a way where I can code it to do that?
The user will still have to manually change the content of the popup, such as the title and the text, but I want to be able to make the links work automatically according to the posts.

Please help me ??