system
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human
How did we get so much water on early earth, if water is so rare on other planets?

My understanding is that we went through a “prebiotic soup” and a “primordial soup” phase in which molecules were floating around getting ready, and subsequently hooking up to make macromolecules, preceding the advent of life. (Correct me if I’m wrong on this! I just learned it today, really.) 

If this is the case, then my question is - how did we end up with the water to make the soup to begin with? 

It seems to me that with the sun being so hot due to the lack of an ozone layer, if water began to form, it would just evaporate, wouldn’t it? 

I’m also wondering how our planet seems to have, perhaps somewhat unusually, developed copious amounts of water when other planets seem to have none. I roughly understand how planets are created - by compressing gases filled with elements…but would that mean that our gas cloud just happened to have significantly more hydrogen? Or is it that our planet’s circumstances/context/mixture of elements helped it to either retain, produce, or excite reactions in hydrogen and oxygen more readily? 

Nobody needs to go through the trouble of answering all of this, by the way…whatever small insights you can offer is very much appreciated! I don’t want to be a time sink.
gpt
We don't actually have that much water on earth, compared to the mass on the planet, water doesn't even make up a fraction of a percent of the total weight.

A strong theory is that earth got its water from impact collision, asteroids and plentoids carrying their own water.  Even without the ozone layer, we've pretty much always had an atmosphere.  An atmosphere of CO2 means the planet gets a lot hotter, but also considerably increases boiling temperature too, more than double.

It's why NASA is so focused on the Habitable or Goldilocks zone, close enough to the sun that water exists as a liquid, but not so close that it won't all burn off.

Because life on planet earth likely evolved deep in the oceans around a type of volcanic geyser, it is assumed all life needs water to begin, hence the habitable zone.

This zone is pretty small, Venus once looked like earth, but was too close and burned up, Mars our next nearest was too far away, and all the water is frozen. Out of 8 planets only one can support liquid water, so we can see why its so rare out there.