As lots of people since at least Chaucer have said, “nothing ventured, nothing gained.” For absolute sure, I can’t earn a living as a writer if I’m too afraid to try. The chances of success are higher if I try. Doing is even better than trying, to paraphrase a certain small green sensei.
So here goes!
You may not be in the exact situation (I can take a big plunge partly because no one is depending on me for basic needs and because I have an established alternate career in teaching). Instead of letting fear of failure keep you from trying whatever it is you know is worth doing, it’s so much more amazing, intense, and rewarding to venture, to take on a new challenge. (And scary, no lie.) Small steps, cautiously, and only for really worthwhile endeavors, but go for it! Ride through the doubts.