Why would you ask such a question when you obviously have done 0 research?
Here is one fact for you to chew on-
Jesus enemies were His witnesses. Those who feared loosing control of the people they held in religious and social bondage could not deny His miracles as He did them openly in front of 10's of thousands of people.
They feared loosing their positions, authority and even the wrath of the Roman government. They very simply could not deny what all witnessed so they decided to blame it on the Devil. Roughly translated they said He healed the sick and raised the dead by the power of the devil in order to discredit Him and who He was.
So even though it was in their best interest to deny Him and the power of God that worked in and through Him they could not.
His enemies were His witnesses.
Where can we find definitive proof that any of the supernatural events in the bible actually took place. If someone can prove, without a doubt, from other than biblical sources, that things like water tuning to blood, plagues of frogs or thousands being fed from a fish and loaf of bread, I'm sure it would go a long way toward getting people to see your side. If there is no scientific evidence, then you have to ask 'Why not?'.