You are Joseph Smith!
I already have proof that God exists and the Bible is true. Unfortunately this proof was given only to me. I can tell you my testimony but it is up to you if you believe me or not.
By the way, "God exists" and "the Bible is true" are two entirely unrelated things. The Bible is provably not "The One Truth", but proving whether or not God exists remains a hard problem.
The only thing that is 100% certain is that what you find in your Bible has been
a) taken from a selection of abrahamic texts, reworded slightly different
b) stolen from pagan stories and beliefs
Seeing as Christmas is nigh, it's worth to mention that both Christmas and Easter are stolen from the pagans, too.
Insofar, what's in the Bible has very little, if anything, to do with what God said or what God wants (if God exists).