Q: When I try to log onto miller or weise using the login and password you gave, it doesn't work.
A: The slip of paper gave the Kerberos password, not a login password. You need to log on to the machine using some existing account. If you don't have one, you can request one from the college or get a class account from the instructor.
Q: How do I change it to something more reasonable?
A: Use
/usr/afsws/bin/kpasswd.uwmcs pantherid