Hypothetically, science proves free will isn't real

[Angrboda]

A choice is free if, at minimum, more than one possible world is reachable [1] from the actual world by a deterministic path [2] including the operation of the will. [3]

Could you elaborate on these 3 concepts?

Is reachable) there exists a path from the starting point to the end point using only available alternatives.
Deterministic path) all alternatives obey the law of determinism, meaning they accord with natural law.
Operation of the will) the human conscious will, which in its operation provides a non-deterministic path among alternatives.

I don't believe we have free choice or free will, but that would be its definition if we did.