Fate or Freewill?

The future is not set (the universe is non-deterministic) but we do not have the ability to change it (quantum randomness does not allow us the ability to change anything). In any case, if the future is not set how does the term 'can we change it' make sense?We have freewill - and would still have freewill if the universe was completely deterministic. We are our brains and bodies, since the actions we take are determined by these parts we have freewill.

Why does God knowing the future imply no free will?

No, that doesn't follow. The past is determined, does that mean we had no free will in the past? Knowing the future merely means that god knows what choice we will make, that doesn't imply that we didn't make the choice of our own freewill.In order not to have freewill we would have to be co-erced into making the choice by things beyond our control, determinism does not imply this. In fact, god knowing the future doesn't imply determinism either; anymore than someone having a time machine does.

By free will I mean that our actions are ultimately determined by ourselves. Alternatives do not come into it. Derivations of free will based on alternatives are Philosophically thorny - how can we know whether or not there was an alternative? If we would choose the same alternative if the same events were run again is it really an alternative? etc. Why cannot we determine the future and god simply know what we will do? Imagine I have a time machine and travel ten years into the future, I now know what will happen in that time (or a small subset thereof) does this mean than everyone at the time I travelled from now no longer has freewill?