From my perspective, you have to consider the nature of causality (or time if you prefer the human measurement of causality). Personally I'm inclined to believe time is little more than a dimension of spacetime, and just like the three spatial dimensions, it has a start and an end (of sorts), and is always in existence. I believe mathematically, physics works as well in both directions, it's only our perception that applies a one-way arrow to time, the anthropic view, but it seems hugely arrogant to assume our perception of something automatically reveals it's true nature. That certainly doesn't seem born out by the advances in physics over the last 100+ years. e.g. relativity and quantum mechanics have both shown our perceptions and intuitions can be wildly wrong.
What if, our perceptions working in a neural network, which is in essence an electrical circuit, only works to produce self-conscious cognition when the electricity flows in only one direction, just like many electronic circuits of all sorts of types. This could mean that our perceptions only operate in one direction of the flow of time?
If this is true (and I don't believe anyone has managed to disprove it yet) then we always exist, we are always there, during that brief span of time (our 'lifetime'). Maybe there's even an almost infinite number of moments during our life when we are aware, Maybe the me of a femto second ago is always there, but can't know of all the others before and after. Feels to be singular, unique, and travelling a path that once past is gone, but before reached doesn't yet exist (to it's perception)? We only perceive things by moving to the next version of us in the progression of time (bear in mind it's seems likely time is granular not continuous - I believe the smallest possible progression of time/causality has even been calculated). Like the frames of a celluloid film, it only makes sense when played, each static moment on it's own has no direction or speed.
This would mean that not only do we never truly die, we are always in existence during that time span and will be forever ('forever' being a rather unhelpful descriptive term, but there you go, humans are not suited to understand this stuff, hence don't have the language to adequately discuss it), but also it would mean that there really is no free will.
It can be argued that quantum 'randomness' would disallow that, due to the unpredictable nature of quantum interactions, but I would argue back, it's clear in the anthropic universe (that which we can natively experience) quantum effects average out very quickly as we move up the scale from subatomic particles. The scale of neurons is pretty large, and can be observed and measured and shown to follow defined rules with those 'random' effects being cancelled or averaged out.
So where does free will reside if it does exist, what is it's actual nature? I'd say that without determining that, any discussion will struggle. One could resort to the supernatural (the 'soul') but the supernatural only begs the next question, what is the nature of the supernatural, where did it come from, how did it come into existence? And so ad infinitum.
I'd judge we may well not have free will, but the inability to determine that experimentally, and the complexity of function that would make it impossible to predict our next actions even if they are predefined, make the question moot. In the end, it's no more helpful than the 'living in a simulation' idea. It cannot be disproved, therefore it cannot hold scientific value as a theory.
Therefore, only non-scientific enquiry could make much of it, and that's so subjective it defeats my ability to consider it seriously - I need evidence and logic, I'm not capable of believing that which has no evidence to base itself on beyond billions of different irrational beliefs. Which one could be correct when there's no way to determine that?