If you have come across some of the threads on this site, which suggest over the top ages of human and Yugas in thousands of years, which will directly contradict the current form of evolution theory, then that doesn't mean that God itself doesn't exist! :-)
By staying in such denial, you are unknowingly raising finger on the cultural faiths & researches worth several thousands of years happening across the globe.
A similar question Swami Vivekananda used to ask people, "Have you seen God?". That stopped when his ultimate Guru Shri Ramakrishna Paramhamsa made him realize. But for that, Vivekananda surrendered and kept his mind open. Later he subscribed to the same philosophy which he used to ridicule. On other hand, Duryodhana did not accept Vishnu's incarnation even after witnessing the event of Vishwaroopam.
A Jeeva-Atma's supreme goal is to get Moksha and that goes through God. It's up to us, which path we want to choose. I would recommend Not be an atheist, who would directly deny God without inquiring more about it. Be an atheist, who doesn't believe God until he has researched it All. This will lead you towards Gyaan marg.
There is 1 sloka in Gita which tells the importance of a true spiritual Guru and you may want to look for it.
Overall Bhagavad Gita Chapter 7 is a good chapter to start for the person with lot of atheism.
All created beings have their source in these two natures. Of all that
is material and all that is spiritual in this world, know for certain
that I am both the origin and the dissolution.
Especially beware of the below:
BG 7.15 & BG 7.25
Those miscreants who are grossly foolish, who are lowest among
mankind, whose knowledge is stolen by illusion, and who partake of the
(atheistic) nature of demons do not surrender unto Me.
I am never manifest to the foolish and unintelligent. For them I am
covered by My internal potency, and therefore they do not know that I
am unborn and infallible.
Even I too believe in the theory of evolution, but then my mind stumbles when I ask myself,
Who created the first living cell among all? Or Who did the current Big Bang?
We don't have to let that rebel die inside us, but calm it down to channelize in a right path. e.g. I finally decided to surrender myself to the teachings of Bhagavad Gita, even though I don't have the proofs of it being true. So that I can backtrack my knowledge based on it.
Also, don't rely totally on the evolution theory, it's just < 200 years old and it itself is slowly evolving. There is a whole section of Sexual Selection in it, which suggests how male & female choose (read lust) their partner based on certain criteria. This might be true, but that's not all.
Here are 2 cents on that!
They say that this world is unreal, with no foundation, no God in
control. They say it is produced of sex desire and has no cause other