is rather exciting, even just to find planets with remotely suitable conditions for life so close to home (that is not in our back yard, that is like on our doorstep!) is very encouraging for the possibility of life elsewhere... Which I'm personally fairly sure there will be, the universe is mind bogglingly big and diverse...
however, at 20 light years if they were as advanced as us we'd know because of the radio waves that would have spread out since 20 years ago.
So for life there, they would think we were back in the 80's lol and they could be as advanced as say the victorians and we'd never even know (complete radio silence!).
but, life on a different planet, hard to imagine what it could be like. There is life on the Earth stranger than our wildest imagination, you can bet life elsewhere will be nothing resembling humans lol