We don’t know.
But we do know the Earth is special. I’m sad to report it is possible we are the only one. We sure hope we’re not the only one. We had high hopes in Mars.
It’s not just about being in the Goldilocks zone around a star. It’s not just about planet size or having an organized magnetic field to shield us from bad stuff coming from the sun.
The Earth got lucky because of a series of cataclysmic events that brought us to the point where we have this life sustaining haven floating in space.
For example, the moon. We need the moon. If the moon flew away, we’d all die. How did it come to pass that we have such a big moon in just the right place to stabilize the Earth?
Well, the latest thinking is that a Mars size planet collided with Earth back in the day and spewed a bunch of rocks and junk into orbit. This stuff coalesced into what is now the moon. And without the moon, nada.
So what’s the chance we can find a planet with those kind of circumstances? Not much.