Free will also isn't real, but I don't go around to people I know and care about trying to collapse their entire world view around it. Sometimes it's better if people believe in fundamentally incorrect things that don't impact others.
Edit: here's a crazy idea, if you think I'm wrong...that's ok. Just leave me be? Maybe? Isn't that the point of my entire initial comment. Lol.
If everything is predestined, whatever you choose is your destiny. Which means you get to choose your destiny. Even if the decision is already determined, your decision process is a part of that and whatever you decide is what becomes the future (or present). Predetermination is irrelevant unless it can be seen beforehand, but if it could, that knowledge could be acted on to change it. So either you can see the future and change it, or you can't so there's no functional difference between it being indeterminate.
If you define "free will" as individual processing of input based on your genetic makeup and past experiences/memories and circumstances, with some inherent randomness. Then i guess free will is real.