Your questions are valid but your answer is only partially correct
There is nobody before Jesus... In other words,, Jesus existed before
he was born. The example of this is.. :
[John 1 : 29 ~ 30]
29. The next day John saw Jesus coming toward him and said, "Look, the Lamb of God, who takes away the sin of the world!
30. This is the one I meant when I said, 'A man who comes after me has surpassed me because he was before me.'
John clearly states that Jesus exixsted before him.. and scientically
it is very strange and unagle to explain.
You can not dissect the bible with modern scientific understanding
Bible says God is in Jesus and Jesus is in God so they are same
But how can two being be one ?
That's Bible for you.. it does not always make sense.. not because
it is false.. but because we lack the inability to fully understand.
You can not expect an ant to fully understand quantum physics..
But that does not mean quantum physics is false...
So.... The answer is ..
1. Noah did not go to hell
2. People before Jesus was born did not go to hell
(if they believed in Yahweh(name of god) in Bible)