Confidence indicates that you trust yourself and your ability to live a productive life. A confident person is capable of new challenges and is willing to take responsibility for all their actions.
Your confidence is increased as you work and live your life to reach success or failure. Each time you succeed, you reinforce your confidence. If you fail, you also reinforce your capability to move forward and hopefully not look back as if failure was a negative thing, just a learning tool.
To be confident also implies that you have courage, which comes from the heart. Your heart and your mind together support your self-confidence.
Courage and confidence are close cousins. One will help you get the other. Tell yourself the truth as often as you can and you will be more confident. Tell yourself lies and you will not move forward towards confidence.
Self-esteem is about how you judge yourself. You can have loads of self-confidence until your inner judge says ‘You could have done that better’. You then may ask ‘Am I worthy?’ If you get an inner response that ‘Yes, you are worthy.’, you will dismiss your inner judge; your esteem is intact.
Confidence enables you to go after what you want even if you think you are not good enough.
Go after what you want, without stopping to consider how well you will succeed. That aspect is what moves you back to low self-esteem and will prevent you from taking any scarier journeys.