Don't doubt yourself. Self-doubt is dangerous and has killed more hopes and dreams, large and small, than failure ever has.
When in doubt, push on. Faith is doubt’s brother.
Willpower and determination, especially when you don’t know the answer, when you don’t what’s ahead, is the mark of a successful person because they strive on no matter how lost or confused they feel. They push on past past apathy, doubt or fear.
That’s what a hero is. A regular person who who, in spite of weakness, doubt or not always moves ahead goes ahead and overcomes anyway.