Every document with multiple pages only downloads the first page. It also downloads to Libra draw.
You’re talking about PDF, I suppose? Please give more details. PDF is not really editable in Libre, but you can do a little of it, but only in Draw.
When I try to download any document only the first page downloads. It shows the number of pages that there is. i.e. pages 1/33. Only the first page is visible.
This does not appear to be an LO problem.
Please give the web site and the file you are downloading.