Interstellar travel is not possible. Not by us, not by anybody.
Even a child knows that people are never going to be able to swim non-stop from (say) Dover to Sydney. And interstellar travel is about a million times harder than that.
People who say, “who knows, in 100 years or 500 we may make a discovery….” are merely dreamers.
One potentially suitable destination is Proxima Centauri B at 4.32 light years. Another is Ross 128 B. at 11+ light years.
That's between 10,000 and 150,000 years travel time at NASA's current top speed.
The dreamer says, “but improvements in speed…..” OK... We double the speed - That's between 5,000 and 75,000 years travel time.
“Generation ships” are the purest of pure science fiction.
On the face of it, it's a good idea until we think about thousands of generations of humans travelling non-stop through space, living on food tablets and recycled water, arguing about who should land the ship after 5000 years of living the life of slugs.
And then... “OOPS, there's nothing here, let's turn around and go back…..”