Think of other things you believe in. You believe in the sun rising in the morning. You believe that pressing the submit button here at JWN usually results in generating a new post. You believe that when you turn the key in your car, it will start. You believe that when you jump, you'll fall back down to the ground again.
Why do you believe in those things? Because you're convinced by the evidence that they exist. And most you have even personally experienced.
Now think of things you don't believe in. You don't believe in the easter bunny. You don't believe in monsters living under your bed when you go to sleep at night. You don't believe that somewhere on the far side of the moon there is a secret special disney space world where everything is free.
Why don't you believe in those things? Because there is no evidence for them.
Now think about God. Is there any evidence for the existence of God? There isn't. Therefore, don't believe in God.