If we could accelerate a habitat to the speed of a voyager probe, then 75,000 years would get you to Alpha Centauri. But you would be traveling 17 kps and the above time interval fails to account for deceleration time to match orbit. Moreover, in 25,000 years, Alpha Centauri is projected to be moving away from us at 45 kps.

But then if we can travel faster at significant fractions of c, even slowly moving subatomic particles become highly energetic radiation. And when we get there, we have no idea what will be found, so be prepared to live on the depleted habit indefinitely.

And Mars will never have a breathable atmosphere. Those gases are gone and will not be re-extracted from the minerals remaining.

Some problems are insurmountable.