I’m quite interested in this topic and how it relates to fate and free will. If we do not live in a multiverse then fate is in fact real, and true free will does not exist. Sounds like a boring place to be but actually might not be as dull as it seems.
On the other hand, if we do live in a multiple world universe then I have a hunch that it just might be possible to influence the course you take between the parallels! I enjoy topics like this - might post about it at some stage if I get the time.
I think even if we live in a reality with only one universe, we still can have free will and fate might not exist.