I reject any scientific basis for answering this question, so whatever my position, I'm not taking a position in regard to the behavior of particles...
That said, this is a richer question than the usual debates about it would suggest. I understand 'fate' negatively and 'destiny' positively, but hold that humanity broadly has control over each for themselves (if our fate is to be wiped out by the death of the sun, or our destiny to find an eternal home in heaven, either of those, and all other possibilities, will have been our responsibility) because we have power to construct and realize those possibilities.
On an individual level, well it gets a bit murkier still. Obviously, on your deathbed, you could call that your 'fate', or say of someone who had already passed that it was their 'fate' to do so, but whether and what form of meaning we attribute to such a happening is also our construction. We have the power to either make necessary or unnecessary each and every event. For related reasons, I do not understand there to be such a thing as individual destiny - all persons have their destiny bound up in human destiny; any talk of my personal destiny will only be my share in the greater destiny of humanity, and it can't be understood or realized in isolation.
As for 'free will' - I find the terms in which that debate is usually couched to be too crude; all I'll say is that from the perspective of possible human experience, I must always choose, and on every level (including the choice of whether to see myself as one with free power to choose, though to me the latter choice would always be one in bad faith). Nothing else matters.
