If I may... the Milky Way's central black hole is like a star in a galaxy, part of a galaxy of galaxies. All observations in the observable universe are within that system.
"Nearby" galaxies of galaxies are on such a large order of magnitude away that we can't see these other systems. This creates the illusion that there is nothing beyond a certain distance away when in reality these systems are simply too far away for our current technology to physically see them. In reality, the universe is infinite and eternal.
For more information, see CascadingUniverse.org
There is also a possibility that there are other universes further outside out sphere of detection that are expanding away from us faster than the speed of light which means to us they don't exist. <3
And yes you may, I'm always up for more knowledge, it is something I can't get enough of. Thanks for sharing and I hope you have a great day. <3