Destiny or free will is a question only as old as religion, and it’s a silly question. In my opinion, this is one of the ways that religion and religious thought sullies the world. Some dead bloke way back when had some seeming epiphany, and it was entered into the doctrinal record.
The concept of destiny is the silliest part. This is a throwback to the teleological notion of progress. I wonder if the whole concept of progress isn’t an offshoot of religion.
I’ve written elsewhere about the folly of progress. Destiny fails on the same level. Moreover, destiny in this context is first about individual destiny—what is my personal fate—and then we devolve further into some group notion, whether by race or nationality or some other social construct. It’s the same logic that led to Manifest Destiny and the slaughter of millions upon millions of people worldwide over the course of history1.
Neither is free will sensible. Humans—living beings, categorically—have some autonomy over themselves. This, of course, presumes self and identity to actually mean anything. But, they are subject to the influences of genetics and environmental factors—including social indoctrination—, so how would one extricate these from some notion of sovereign free will?
One does not even need to be a strict materialist to see that one does not have free will. Not even Sartre’s no excuses Existentialism fully accounts for this. An Existentialist might argue the despite whatever historical baggage yo carry with you to any given point, you can always decide on what your next point might be. But this misses the point that any decision one makes can only be made in context to the experiences you’ve already had.
So, as I said at the start, the question of destiny and free will are for juveniles. There is no reason to adopt the religious frame that makes them appear to be more than the specious notions they happen to be.
In the end, you just are. Enjoy the moment or at least just live it. It may be your last.
1. Please note the I am using the course of history in the idiomatic sense as one might employ corners of the earth. There is no course; there are no corners.