Do you have a predetermined fate? Yes. You do.
I don't just believe it, it's really the only logical option.
Basically, yes, you have free will to do whatever you want, but you will always want the same things.
All things in the universe are mathematically predetermined based on physics, and geometry. Anything in the universe that is seemingly random or based on a probability becomes a complete certainty if you have enough information about the universe to see all of the factors.
It is COMPLETELY beyond the scope of human understanding to be able to access, absorb, and/or comprehend the degree of information requiered.
But, IF there was a being who could calculate the trajectories of every subatomic particle, work out the subsequent chemical and atomic interactions between them all, etc etc etc, that being would be able to calculate the growth and outcomes of every subsequent firing of every synapse in every brain, and the resulting thoughts, impulses and decisions that every being in the universe will make.
That being would be able to calculate every event from now to eternity.
Since that level of awareness and thought is utterly beyond the scope of any creature that exists, for human understanding we instead boil all that information down to probabilities, broad generalizations, and the fundamental physical laws that govern all of those calculations we don't have the information and scope to work out.
It's like an ant trying to comprehend how the city it lives in is run. The information is there. Humans understand the systems and can tell you what the outcomes of things will be in accordance with city ordinances and such...but to the ant it's something utterly beyond it that it will simply never be able to fathom.
The ant will react in certain ways to whatever happens to it, never knowing that there's a system governing what happens around it.
People can't possibly understand the ultimate complexity of the mechanations of the universe, so we all have to just do whatever it is that we're going to do, not ever really consciously aware that the system we live in utterly governs the infinite web of chain reactions that result in anything that ever happens and everything that ever is.