If you imagine that a group of 3000 people traveled from Earth to an alien solar system for 50 or 80 years aboard a large spaceship, and children were born on that spaceship during the journey there, then maybe you can also imagine that these people are actually pretty used to living in space. Interestingly, it could also be possible to land a ship on an asteroid, attach engines to the asteroid, and turn said asteroid into a spaceship or space station. You could park your space station 500 kilometers away from the nearest asteroid, and have robotic probes fish asteroids back by securing them with giant nets and slowly reeling them in, without any humans needing to leave the space station and without needing to accelerate the asteroids to dangerous velocities.