So...god already knows what will happen in the future. And god is infallible so that means you can't change it...so does free will actually exist? [Spirituality & Religion]

Free will doesn't exist. However, "knowing what will happen" ie. omniscience doesn't equate no free will, although it gets pretty meta. Particularly because omniscience isn't something that exists in real life, so it's hard to reason about it with no practical comparisons. Votes in some countries come close, you're free to vote who you want, but the powers-that-be already know who will be elected ;)

However, when you add omnipotence, you get the usual problem of how can omniscient, omnipotent God create Devil & sin while being infallible & devoid of evil. The usual argument is that he somehow, still created free will and that is not evil, leading to the question of ethics of knowingly creating so much suffering. But it's turtles all the way down.