>>79153502To begin you can just look for "online web crawler".
Program versions are better, but I haven't used it since I changed PC and I forget what the one I used was called.
Essentially it just gives you all reachable urls a website has.
So if they have, for example, a public accessible FTP page, it will find it.
I was able to find internal documentation for a local printer company detailing some advanced troubleshooting steps and more recently, I was able to upgrade my internet from about 200KB/s to 4MB/s by accessing an internal ticketing system and manually starting the process to upgrade my street's cables, after months and months of being ghosted by "normal" channels.
