dynamic scroll list of files

hello,

I would like to create something like shown in the picture.

How do I apply adding new item to the list on clicking Add scene button? I just want to reload the list and scrolling bar on add scene click not update whole scene (if its possible). I wanna read possible selections in list from folder files.

I cannot open the tutorial "creating-scroll-lists-at-run-time", is there any replacement for this tutorial?