Know what you are getting into
For the interview make sure you know the course, i.e. stages, tests, licences. Then know about the career you are hopefully going into, i.e. hours needed to unfreeze ATPL, hours need to be considered for captain, where do you expect to be in 10 years etc.
Don’t try to 'blag' your way through, the guy (or girl) sitting in front of you will be a current commercial pilot! and will see right through you.