Confidence doesn't come from believing in yourself. It comes from having done the uncomfortable thing enough times that your nervous system stops flagging it as an emergency. Because nothing is actually hard, it's just unfamiliar.
I don't know who needs to hear this, but most things in life are more achievable than we think. If you decide what you want and go after it with full effort and intensity, the world will bend to your will far more easily than you might expect.
I believe movies are so underrated. you should watch one incredible movie a week to completely change your perspective and put you in a new mood. it works wonders.