We can reasonably send something to Alpha Centauri in 100 years assuming you can get the drive to work, but that’s the closest star to us, and Project Longshot

We can reasonably send something to Alpha Centauri in 100 years assuming you can get the drive to work, but that’s the closest star to us, and Project Longshot was a design for an unmanned probe. Yes, the British Interplanetary Society did do a study on what a manned mission might be like, but they always seem to underestimate the biological problems of space flight. If you wanted to colonise a planet around a nearby star it would be a truly staggering undertaking, even getting the fuel for an unmanned probe probably require H3 mining of Jupiter.