You and I are humans who live in this universe. You either accept that this universe has no creator, or you do. I am one of those who believe the universe has a creator, and that it is our purpose to find Him.
Finding Him is finding truth, and finding truth is finding Him. The two are inseparable. Once you know that there is a creator, there is nothing else to do but to submit to Him, to become one with Him.
This way of living is known as Islam, an Arabic word which means "submission."
It is not a new concept, it has existed for thousands of years. Those who are good are those who walk towards God, and therefore, they will be rewarded. Those who walk away from God and walk away from truth, they create their own hell. God will remove people from hell whenever He sees fit.
Islam is not really a religion, it's a way of life, it is a state a person achieves. God is the one who decides whom is ultimately a Muslim and who is not. Even an atheist can be considered a Muslim in God's eyes, because they lived their life in accordance with God's will.
Some things to know.
The universe is indeed billions of years old, and evolution is certainly one of God's ways of creating life, including humans.
The Qur'an is the final scripture revealed to mankind, and the final law for everyone in the future. This book contains all the details for the person who desires to follow God in the best of their ability. There is no need to go outside of the Qur'an to "complete" the faith. The book is sufficient.
Those who kill in the name of their beliefs, they go against one of the most basic fundamental laws of God, to not take innocent life. So terrorists who act in the name of Islam are people who do not truly represent the word of God.
Last thing to say, our life is temporary, that's obvious. But be wary of the fact that, whether you believe you will be born again, or you won't, you shall always strive to do good, and refrain from all things evil.
That is what I am trying to do.