AB,
I could ask you how you chose to write the word "how" in bold capitals.
You could, and you'd get the same answer you always get and that you just ignore. That though would be just another evasion by you of the question
you were asked about this supposed "soul" of yours. Is "it's magic" really all you have?
Really though?
It certainly was not random.
No-one suggested that it was.
But at some moment there was a consciously made decision to write it in bold.
Yes, as a functionally useful model that's true - though that says nothing at all about the explanatory model that underpins it.
Was this decision absolutely predetermined by every event which has occurred since the beginning of time?
At least until you get down to the quantum field level, probably yes.
If not, what was the determining factor? And what determined that factor?
See above. So about the question you were asked and yet again you've just avoided...
HOW would this "soul" of yous function if not deterministically
or randomly?