Lightbox gallery opened from button

I want to open a lightbox with images from a button. I don’t want the gallery to be visible on the page. The lightbox needs to display previous/next controls, to scroll through the images.

The result should be similar to this:

But opened from a button, and without displaying the image grid on the page.

My knowledge isn’t strong enough to understand how I could skip showing the grid of images, and instead load this from a button. Any help is highly appreciated! I’m pretty new to this, so bear with me…