. I went on to the server and found the password.bak file mentioned, but I don't think we are allowed to access it.

Don't assume things -- try it out. You will get an error message for opening a file you don't have access to.

I'm kind of curious how I'm supposed to interact with this file in my program if I can't even view its contents.

If you really can't read it, you can't. Then approach your tutor and ask him what's wrong. But try first.

If anybody could direct me to some relevant tutorials or give me any kind of help here at all I'd greatly appreciate it

perlintro, http://learn.perl.org/, Tutorials