I don't have a workable theory (nor does anyone else) on how The Universe came into being. I understand The Big Bang but the question remains is what created the singularity that started The Big Bang. Additionally, The Universe must be endless, in both space and time, else we would have to explain what existed beyond the periphery of existing time and space. There are many unanswered questions and none of that precludes the existence of a divine being. When it comes to the creation of The Universe (not just OUR Universe), there is equal evidence for both a natural or supernatural origin -- that is no evidence at all.
However, When it comes to the development of life on our Earth, the fossil evidence that species evolve and even become more complex over time is indisputable. Are there unanswered questions? Of course. Can we prove it by experiment? That remains difficult due to the extreme time scales and randomness involved. But, we understand both biological forces behind evolution and the discovery of DNA and our ability to catalog DNA only continues to support evolution as the driving force behind development of life on this planet. Evolution is, to put it bluntly, the best theory fitting all the known data. No other theory can even compete with it.
Belief in a deity doesn't preclude a belief in a natural explanation of life on Earth, or vice versa. There is absolutely no reason for naturalists and theists to be at war with each other. At the end of the day, our beliefs, one way or another, don't impact anything or anyone. Life will continue to evolve as long as there is an ecosphere to sustain it and we are merely a bus stop on the way to whatever may be the final destination of life on this planet.