Here are some tips to conquer fear:
Then write down a plan for how you can come back from such a scenario.
By sharing and by getting some input from a levelheaded friend or family member he or she can help you to alleviate the fear and inner pressure. And you can gain a much healthier perspective on things again.
It is a natural impulse to try to deny the fear when shows up in your life. Perhaps you try to not think about, you try to push it away. Or you tell yourself that you need to focus like a laser beam on the positive.
You don't have to go all in at once in many cases. Think about how you can move in small steps and slowly towards what you want. Just dip your toes in at first if that feels more comfortable. The most important thing is that you start moving and that you take action, not how fast or how much action you take at first.
If you for example want to start your own business work on that in the evening while still working at your day job or staying in school. Don't let thinking like "I have to go all in and take huge risks" hold you back.
By not making this into a huge thing you have do but instead just a small step, that you can take and get done as slowly as you like, it becomes so much easier to do what is most important at first: to put yourself in motion.
Then, along the way, you can take bigger leaps if you like and speed things up. You will learn through successes and failures (and realize that you won't die if things don't go your way all the time). You will quit some things and continue doing other things.