Courage comes before confidence. Courage is feeling the fear and moving ahead. Courage is continuing to step ahead in spite of fear. When you face the fear and overcome it, you build courage.
Courage gives you confidence to take on new ventures. You gain confidence only when you do things you know that you cannot do. But you take the risk of doing it for your own good, when you do it again and again with minor improvements and victories, you gain confidence. Confidence is not something that is in-built and comes out of the box for anyone. You get confident in something when you expose yourself to the situation gain and again. You build confidence brick by brick and step by step. You build confidence by small victories achieved over a period of time.
The more hard stuff you do the more hard stuff you can do. The more you do something that scare you, the more you get courage and confidence to handle stuff that makes you nervous. The more confidence you gain, the less anxious you become in handling uncertain things in life.
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