Even if there are other planets with breathable air on them, we aren’t going to get to them unless we can create a “Jump to lightspeed” transportation system.
We can’t even get our subways to work in DC.
It’s gonna be a long time before we go out into real space and even if by some chance we reached a planet after many generations of travel, I doubt that anyone will know about it for many years.
Meanwhile back on earth, “Houston, we have problems” and they need to be solved now.
Physicists around the world are busy cracking that enigma as we speak:
It's only a matter of time until our species hacks the code of the physical universe and creates FTL. I fully expect that our great grandchildren will live to see that breakthrough, provided we don't destroy ourselves first.