At the end of the day, all you can control is what you do. And all you can do is to behave in such a way that aligns with your core values, with what you want to achieve, with everything that matters.
Of course, this is something you have to figure out. The sooner, the better. It requires time, trial and error, failure, commitment. But once you are there, once you know what will make you sleep well in the night, just stick with it. Forget about the rest, forget about the others, and most importantly forget about the outcome.
Just stick with it.