This is a very good question Mussette.
When I read this question for the first time - WHAT makes you feel confident - it is asking us for outside source of our confidence. In my view that is contradiction.
What would happen if we are getting bad feedback at work, or being back stabbed or having deceiving friends? Or if we lose our job and money is tight? Then we still need to be confident that you will find a job or be confident that you can improve your performance or have a confidence to evaluate some of our relationships and release negative ones from our life and find new positive connections.
So confidence is in my view, believing in yourself and not validating yourself against external influences. t is knowing yourself as well, so knowing where are your weaknesses and strengths so you can recognise if feedback you are getting is genuine and true.
So it is innate and you have to work on it - getting to know yourself. I learnt through interactions with different people - ones that were really good and deceiving ones. I think I learnt a lot from deceiving ones
