Your probably best just going to to the first training session/introductory session with an open mind about what position to play. It's almost impossible for us to say without seeing you play. We're not sure how quick you are, what your feet are like, how good your handling is, what your passing is like, how good a tackler you are, and what your aggression and confidence is like. As BG8 has said, you could theoretically play anywhere in the backline, or on the openside flank, all depending on your skillset.
The coaches involved with the university team will assign you a position based on these / what's needed in the team, and you go from there. If your pace is decent, this will most likely be on the wing, because it is the least technical position on the pitch in terms of attacking and defensive alignments etc. As this appears to be a new sport to you, you will find that as you learn the game and your skills improve you may be tried in different positions.
You are unlikely to play at 10 though. This will probably be reserved for the players who have been playing for a number of years already.
Good luck and have fun.