What year are you in school? Or have you finished school?
Do you know the nominal balances of all accounts? That's pretty basic so you probably do, but if you don't that would be number one. Do you know how to prepare an account reconciliation? Can you reconcile cash? Those would be two first level functions I would expect you to know.
IMHO, all account software is basically the same. I've never understood why people worry about which software you know in an interview. Once you understand how one SAP system works you can figure out the next one pretty easily.