1. RELIGION AND SCIENCE DO NOT WORK TOGETHeR. RESURRECTION OF THE DEAD, TALKING DONKEY, TALKING SNAKE, THE FLOOD, AND BIRTH FROM A virgin.
2. Failed Bible prophecies. Yes, Christians use that "prophecies of the Bible are true" which isn't even true.
Destruction of Tyre
For thus saith the Lord GOD; Behold, I will bring upon Tyrus Nebuchadrezzar king of Babylon, a king of kings, from the north, with horses, and with chariots, and with horsemen, and companies, and much people. He shall slay with the sword thy daughters in the field: and he shall make a fort against thee, and cast a mount against thee, and lift up the buckler against thee. And he shall set engines of war against thy walls, and with his axes he shall break down thy towers. By reason of the abundance of his horses their dust shall cover thee: thy walls shall shake at the noise of the horsemen, and of the wheels, and of the chariots, when he shall enter into thy gates, as men enter into a city wherein is made a breach. With the hoofs of his horses shall he tread down all thy streets: he shall slay thy people by the sword, and thy strong garrisons shall go down to the ground. And they shall make a spoil of thy riches, and make a prey of thy merchandise: and they shall break down thy walls, and destroy thy pleasant houses: and they shall lay thy stones and thy timber and thy dust in the midst of the water. And I will cause the noise of thy songs to cease; and the sound of thy harps shall be no more heard. And I will make thee like the top of a rock: thou shalt be a place to spread nets upon; thou shalt be built no more: for I the LORD have spoken it, saith the Lord GOD.
( Ezekiel 26:7-14 )
That was an example. More available here:
Failed biblical prophecies - RationalWiki
3. Religions in a nutshell.
If you would be born in Iraq, you would most likely be a Muslim. Maybe in Africa some follower of pagan god(s). Etc. If God is real, then why not Zeus?
4. Bible contradictions.
Quiz Show (Bible Contradictions) - YouTube
5. Jesus said I am coming soon and the Christians for over 1500 years were thinking that He is coming soon.
And so on. Sorry, I'm just 15 years old, I study economics which really hasn't anything to do with creation or evolution whatsoever, and I'm not really fluent at English.