Action cures anxiety. Sitting around doing nothing but thinking about what might go wrong produces anxiety. A lot of times, the possibility of what might happen is actually worse than what does happen.
The best way to improve your situation is to do what you can. Affect the things that you can control, but don’t worry about the things that you cannot. Those things will happen one way or another and there’s nothing you can do about that. And that’s OK.
When you’re feeling lost or stuck, get moving. Take action. If it is productive action, it may move you closer to your goals. But even if it is not directly productive, it may still alleviate any anxiety you have just by distracting you.