Imagine two old ladies, Maevis and Enid. Maevis and Enid both love to bake, but Maevis only bakes for competitions, whereas Enid does it for her grandchildren. One day, Maevis comes up with a brand new, prize winning recipe for the most amazing cake any judge has ever tasted. So Enid, keen to please her grandchildren on their next visit, asks Maevis for the recipe. So Maevis writes something down on a piece of paper and hands it to her.
The next day, Enid grabs her usual cake making equipment and reads the piece of paper. On it are the words "Maevis' cake recipe: If this cake did not exist, you would not have been able to eat it."
In the paragraphs above, you have an excellent picture of the so-called "anthropic principle". In answer to the question of why the universe is so well-designed for life, atheists simply state the obvious: if it were not, we wouldn't be here to observe it.
But much like Maevis' silly recipe did not explain how to make the cake, so also does the anthropic principle not explain why the universe is fine tuned for life. Everyone on the earth has the wisdom to know that if we weren't alive, we couldn't ask questions, but the simple fact that we could not ask questions if we were not alive does not answer the question as to why we are alive. If you try this kind of reasoning in any exam, you are guaranteed to fail.
"Ok Stan, what do we do at a red light?" "Well, if I hadn't reached the red light, I wouldn't be able to ask that question." Do you want that student on the road?
"Ok Doc, how do I go about getting better?" "Well, if you weren't sick, you wouldn't be able to ask that question." Do you want that doctor caring for your health?
"We need to find out how this guy died." "Well, if he wasn't dead, we wouldn't be asking this question." Do you want these crime scene investigators on the police force?
I could go on. From cake recipes to full blown brain surgery, the fact that we would not be asking the same question in a different scenario does not answer the questions we are asking in the current scenario. Yes, it's true, if our universe was not fine tuned for life, we would not be alive in order to ask why it is fine tuned for life. That is so blindingly obvious that it doesn't even need a name. But that does not answer the question as to why the universe is fine tuned for life.
The obvious answer to this, and it is becoming increasingly more obvious as we see just how impossible life truly is, is that we were put here for a purpose. Put simply, the Creation account given in Genesis is 100% historical. Mankind was put on this earth with the intention of glorifying the God whose image we bear.
But glorify Him we do not, and we taint His image on a regular basis. Because of this, we all deserve God's eternal wrath. But God is not willing for this to happen to anyone (2 Peter 3:9), so He sent Jesus to take that punishment for us. If we confess with our mouths that Jesus is Lord and believe in our hearts that God raised Him from the dead, we will be saved. If this offer had not been extended, we would not be able to answer it.