There is no destiny and there is no fate, but I believe in both.
It is impossible to change your destiny. If you believe you have, it only means that you didn’t really know what your destiny was. By definition you cannot avoid your destiny and you cannot change your fate, because whatever you do or become means that that was what you were destined to do or to become. Your fate is what happens to you.
Does this mean that everything is fixed in the world and you can’t do anything to change it? If you believe that, and so you give up on life, then it was your destiny to do that, but if you don’t and choose to continue living life then that was your destiny.
It is a paradox but one that contains no information and holds no problem to resolve. To me questions of fate and destiny don’t matter at all since they are concepts defined only by what happens, not what is meant to happen.
Though it may imply a fixed universe, it just as easily implies the other. Nothing is meant to happen, it just happens. It is Douglas Adams’ tautology that is “the prime cause of everything in the Universe“, “anything that happens happens.”
The world is ours.