Changing belief systems

Hello coaches

Brooke talks about changing our existing beliefs and we can choose to believe whatever we want. Since childhood I have been taught to be strong and face failures bravely and this stops me from expressing failures and actually getting scared of it. I always want to show myself strong and not want to look weak in front of others. Since these beliefs are so strong in me sometimes I have doubts like probably it will really take a long time to change such beliefs since they have been with me for long time. Probably it might sound silly. Does it take a really long time to change old belief systems.