That’s not phrasing the argument correctly. That’s how an atheist would frame it to try to make it seem unreasonable.
We believe in God because we believe the evidence for him (outside of the Bible or any other holy text) to be incontrovertible. There is existence, which demands a creator (since something cannot create itself). Knowing that an exterior creative force is necessary, we call that force God. Now that we believe in the necessity of God, we seek to know Him better. Knowing that God exists, we can then conclude that either he would reveal himself to us or he wouldn’t. Given that he took the time to create the universe and allow for our existence, I personally conclude that he would chose to reveal himself to us in some manner. At that point, I begin to look at the various religions and religious texts, and consider what they say about what I know of the God that must exist by observing His creation. In the end, I chose to accept Catholicism because it was the one that made the most sense to me, and that had the strongest historical arguments for its Truth (Starting with Judaism, and continuing through to the present day in the Church.)
I didn’t start with the Bible, so it’s not a circular argument. I believe in God because I believe that he -MUST- exist, and I believe in Catholicism because they present the most historical and rational argument for a belief structure. I am either right, or I am wrong. That is something we cannot determine absolutely until we meet God face to face. Taht does not make the belief in Him irrational though.
The countless miracles don’t hurt either