The brain is an advanced computer, nothing we've ever built can compete with it. What you program into it, you become. Allow good things, good things will follow. Allow bad things, bad things will follow. The information you feed your brain is important. Be conscious of what you let in your mind.
You get to learn about the world and about yourself. How do you react in uncomfortable situations? Do you have the courage to do new things? Do you allow things to happen to you, or do you go out there and make things happen? Every day it's a new question.
It's important that if we want to make a change in our life, we have to show up for ourselves everyday. Do the hard things until it becomes easy. Make it a priority. Make it a habit. Make it consistent.