Do you believe in UFO’s or non human intelligent life?
I'd say extraterrestrial (ET) non-intelligent and lower intelligence non-human lifeforms (living or evidence from long past) are plentiful in the universe. But
advanced intelligent non-human life is magnitudes less likely out there.
Therefore, it's not likely any of the plethora of UFO's reported are of alien origin.
Here's the TL;DR part LOL:
Earth has plenty of non-human lifeforms, many considered very intelligent (dolphins, ants, etc). Over a million different lifeforms from microbes to gnu's to whales currently reside here.
We classify these as no intelligence or lower intelligence as compared to ourselves. We can, comparatively, say humans are advanced intelligent life. We are 1 in a million+ of all lifeforms on Earth advanced enough to wonder about the stars and are capable of trying to reach 'em.
I'm thinking a similar disparity of '1 in a multitude' of advanced ET lifeorms ratio applies universally. That's because I believe humans, being as advanced as we are, are a fluke. Just an accidental by-product of past extinction events.
Consider if one major event would have happened (or not happened) in our distant past, humans probably wouldn't be advanced today. Possibly wouldn't even exist. Another lifeform would be a dominant one today, just not advanced enough to do what we do ("Yo, T! Yeah, you, Rex. Hand me that spanner wrench, you silly lizard you!").
Advanced intelligence isn't guaranteed at all in the universe. We're here because of clueless, do-da, chance.
But odd chances do happen. Our galaxy has about 100 billion stars. There are about 2 trillion galaxies out there, each with, say, about 100 billion stars. I'm guessing each star probably has 0 to 9 planets. With that sheer crazy big number of stars/planets out there, some advanced civilizations may still exist, or may have developed and died out already.
Would you want to know the answer if available?
Heck yeah! That'd be so cool.
How much would confirmation change this?
Wouldn't change it at all.
Bonus feature: Here's a video (2min 18 secs) from National Geographic covering extremophiles, life that exists in extreme environmental conditions on Earth. These give scientists clues about how life can possibly exist in the extreme environments of other planets.
Extremophiles 101