You can’t change the possibility. There’s nothing to fear if you are aware that the chances of success is not a 100%.
But even for 1% chance, what would be the best thing you would do in order to achieve that? That at least you’re able to tell and do what you can.
And if there was failure or rejection, despite giving it all, what you had is a valuable information that would help you in your journey.
And another piece of advice, in order to possibly acquire valuable information, you need to be present enough and mindful enough while you are in those moments.
Meditations, Letters, and Metaphors 