What is after Space and the Galaxy?
More of the same, or not.
We can only comment on what we observe, and speculate (poorly) on what we have not yet seen. How do you define (or observe) TOTAL "space"?
We know that there is significant space between bodies in a solar system and even more between the star systems of a galaxy. In between, we can still find traces of matter and/or energy.
We know that there are many galaxies and that they are separated by even vaster distances. We cannot "know" what lies beyond what we can see. Does the universe of galaxies go on forever? Is there an even larger, incomprehensible gap between this universe of galaxies and another one, or more?
We do not know... that is one reason that we are still exploring!