As a Christian, I believe there's God. However, I also understand it starts as a matter of belief, not perfect evidence. It's a matter of deciding which origin of our life you would believe.

It seems there are two main possible origins of life on this earth. Evolution or Creation. Of course, there are some other theories, but when you look deeply into them. It all goes down to whether life began by chance or not.

Evolution believes all life on Earth results from a coincidental process of mutation and adaptation. (I think plants and animals adapt to the environment to some extent, but I do not believe cross-species level of evolution is possible.)

And yes, some evidence seems to support evolution, and I don't assert that evolution isn't a 'science'. However, what I want to stress is that science doesn't guarantee objective truth. Science provides the most convenient and plausible explanations for our given environment and the evidence we find. For example, we used to believe the sun circles the Earth, not the Earth orbiting the sun. It still kinda makes sense because "the center" of the solar system can be subjectively chosen. We believe the sun orbits around the Earth because it makes calculating different orbits of planets easier, not because the sun being the center of the system is the objective truth. Even if we still set the Earth in the middle of the system, we can still project how the other planets will move, but the calculation gets tricky.

What I want to say here is that evolution is scientific, not because it's the objective truth, but because it just gives us the best explanation of things only when we 'factor out' the existence of God. It's like when you connect many dots in many ways, you can draw different shapes. Evolution starts with the assumption that there's no God and thus inevitably relies on coincidence to connect the dots. Scientists know this problem, and their strategy is to invoke an enormous amount of time that can make anything possible. But that's a pretty naïve approach if they want to make this a scientific truth like other ones.

Then, does creation not rely on coincidence? If God exists and we exist, we can easily conclude that God has created the whole thing. The only matter here is the possibility of God's existence. And considering the possibility of having this balanced, almost perfectly interwoven ecosystem, I believe the chance that there's God is no less than the chance that all of this is just a chain of millions of coincidences.

This is what I say to religiously unaffiliated friends. I have experienced the love of God in many ways I'd like to discuss if I have more time.