Not tried this but.... Instagram Graph API - Instagram Platform - Documentation - Meta for Developers
There should some example already on the forum showing a few ways ,like:
but it really depends on who is doing the uploading and how and to what the server allows. Is this internal use/external use so on.., If the directory cannot be read directly from a browser ( for what evere reason ) then there is php that should be able to lsend back a list.
Again I think examples are around.
A very simple way would be to have a directory on a server with the images and a json file listing them.
But as I say more info on the setup would help someone help you 