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.
They don’t tell you this but your walk with Jesus will be messy. You will break down, you will cry, you will get angry, you will be frustrated, you will deal with doubt, you will deal with unbelief, you’re gonna mess up, you’re gonna do things you later regret. But through all this Christ will not leave you, and you will be sanctified through your trials. So if you were expecting a sunshine and rainbows walk with Jesus you are sorely mistaken. The storms will still come, but you’ll have God with you every step of the way, and your joy will be full when you come to terms with the fact that this is sufficient.