Sync to windows file server windows retain permission

Hi All,

I’m newbie to nextcloud. Due to covid-19, we recently need to setup nextcloud and point to our fileserver

My idea is, I want user login to nextcloud portal hosted in the server(in office) and able to continue to work. Now I’m able to use external storage ftp to fileserver but permission is not retain. I want user have to same permission that already set in fileserver. They login using their AD username, then have their own folder that same like how we map network drive for them