Many years ago I read a book called Feel The Fear and Do It Anyway by Susan Jeffers. You can still buy the book today.
What I really remember most from the book is the title FEEL THE FEAR AND DO IT ANYWAY
There are a lot of things in this world we can be fearful of but unless we actually do ( at least some of) them we might as well store ourself in a cotton wool filled box and do nothing.
LIfe is all about taking risks so sometimes we just have to bit the bullet, feel the fear, so acknowledge that it is scary, and just do it:)
Here is an abstract of her book http://web.iitd.ac.in/~prbijwe/Book_Abstracts/Feel%20The%20Fear%20and%20Do%20It%20Anyway.pdf and it is available on Amazon.
For me, fear comes mainly from unknow.
With that in mind, a lot of situations about life are bringed to us to think, for example, i quit of my course on the university after 2 years of study, and by that moment, i was with no job experience as well. So, i was pretty scared about it, what is going to happen? Lefting a prestigious public university?
After a couple a months i got a part time job, and i developed on it and as a person. Now i'm back to university (in other course) and working in a full time job.
I'm not recommending to just do it an see what it gets, as i did, but if knew better the possiblities and consequences, probably i would make better plans and felt less stressed about the situation.
You are right ,it s about lack of selfsteem ,that we need to improve it.
I dont think if we think about it ,help us to cross it in my opinion we have to face with our fear and do it ,then we gain more selfsteem and conclusion will be power of making decision and decrease our fear .