One can become fearless when a person becomes confident in ones own self, As said in Bhagavad Geeta verses 3.42, 3.43 and 6.5 (shown below). One has to understand true nature of oneself, one has to believe in oneself, one has to become confident in oneself and then one has to understand that oneself as soul is capable of controlling mind and fear is just the quality of mind and oneself has to control and guide the mind. Bhagavad Gita: Chapter 3, Verse 42: (says oneself is higher) ones senses are superior to body; mind is higher than the senses; intelligence is still higher than the mind; and Oneself(Ones own soul) is even higher than intelligence and other things. Bhagavad Gita: Chapter 3, Verse 43. (says oneself is higher and oneself has to control mind & senses) Thus understanding oneself to be higher to senses, mind and intelligence, one should control the lower thing by the higher thing. Bhagavad Gita: Chapter 6, Verse 5. One should raise one’s Self by his own mind, not allow to degrade himself. The mind is the friend of the self, and his enemy as well. ( this verse says one has to believe & have faith in oneself and should not degrade himself by thinking himself as incapable...) In 9.22, Lord Krishna says "Whoever is ever integrated in Me and worships Me, I provide him what he lacks and preserve what he possesses." So we can see if we become integrated with Him and worship Him, He will surely take care of us. In that way we will become tension free and fearless. So one has to be confident & steady in oneself without this one cannot be courageous.