Cantwaittodie
First of all, please wait to die! You are here on earth for a reason and live it out!
Now, about your professor. First of all, he is not an athiest. He may want to be, but he knows there is a God.
Here is something from my own life I think demonstrates the answer to his question, though. When my children were little, about four years old, and it was time to start giving up naps, I would give each of them, in turn, a choice: do you want to take a nap and then stay up later with Mom and Dad tonight, or do you want to skip your nap and then go to bed at the regular time?
Total free choice for each of them. No pressure from me at all, for I did not really care what they chose -- I could live with either one.
But I knew each of my children well enough to know exactly what they would choose. I knew which ones, choosing no nap now would then put up a truly mighty fuss at bedtime, too!
But I never forced the choice. It was truly free.
God knows us much better than I know my children, or knew them then (they are even more mysterious to me as adults!). So of course He knows which way we will choose at any given time, but that does not negate the fact that our choices are totally up to us. We do, indeed, have free will.
If we did not have free will, it would be impossible to love God or each other, for love programmed in is not love at all. Love is the free decision to care for another over and above one's care for oneself (or at least as much!). And love is the core of the two basic commandments, which are found, by the way, in both the Hebrew Scriptures and the New Testament. We were born to love. But that requires God in us because of our sin natures. Nevertheless, love is the reason we exist, and therefore we must, of necessity, be creatures of free will, or we would never be able to love.
Hope that helps.