Why are you religious and the atheist line?

Shalom Rabbi. Thank you for all you do…
Every now and then I listen to the atheist talk shows, 
Which essentially asks the callers: What is your proof that God exists? But what actually bothers them is, why are you religious?
I wanted to ask a very general question: In your opinion, or rather according to the Torah, should there be one answer to this question for the entire religious and ultra-Orthodox public, or can everyone have a different answer? And is your answer the entire trilogy you wrote?