How to make lightGallery open 1st image?

Question

JPEG

Hey! Please tell me how to make lightGallery open only one image in full screen without the ability to scroll and load other images?
The logic for a gallery of 20 images: opened the picture in full screen, looked at it, closed it, and so on ....
For me, the functionality of this gallery is important, but because it collects all image elements by class when opening in full screen , a very large list of html code comes out.
There are more than 1000 pictures in my gallery, I optimized everything and it remains only to deal with this ... I looked through all the documentation on lightGallery, but I did not find an answer to this one. Maybe someone faced a similar problem. In English. I didn't find an answer on the website either. I will be glad for any help