Before Noah’s flood, there was a large amount of water above the atmosphere which may have taken the form a ring. There was also more water below the surface of the earth than there is now. That is where the water came from.
Before Noah’s flood, there were no seasons. During the flood, the axis of the earth changed. This resulted in water congregating in the polar ice caps. If the ice caps were to melt, the earth would flood again.
But God promised not to allow that to happen. He has reserved the final judgment of the earth to be by fire rather than flood.
All of this is in the Bible. (The polar ice caps are not specifically mentioned, but the gist of what I am saying is from the Bible.)
Yes... Old Testament... Talks of YHWH 'heaping up the waters in storehouses'... I'll try to find it... probably Job or Psalms...