One misconception that prevails around black holes is that they are akin to some large vacuum cleaner in space, sucking up all material in its surroundings. This is in fact false, since black holes do not act any differently from normal stars, at least away from their immediate vicinity. If it were the case, none of the known large galaxies would exist, since a supermassive black hole is thought to exist at the core of each such galaxy!
Our galaxy’s supermassive black hole is no different in this regard. Stars orbit Sagittarius A* at relatively small distances at the galactic core with stable orbits, meaning that they are not being drawn in by the black hole whatsoever. Just like stars keep planets in stable orbits around them, supermassive black holes keep the rest of the galaxies’ stars, other black holes, nebulae and dust in orbit around them. It is only when something gets extremely close to a black hole that it would not be able to escape, due to the black hole’s immense gravity pushing the escape velocity past the speed of light, making it impossible even for light to escape.