Gallery Link code OR Single image gallery preview

Is there a way to link to a native WP gallery? I can’t use the shortcodes and would like to link like this:

<a href="link to gallery" rel="lightbox"> IMAGE </a>

Or, alternatively, is there a shortcode that would allow me to show 1 image to start. Then, when the user clicks on it, they cycle through the gallery in a popup.

Thanks!