The universe would seem to be a bubble within nothing, expanding into nothing, but, again, ‘nothing’ would not seem to be, or there, so the universe grows within itself. The universe is still that which changed into its expanded form, and ever reflects its properties, such as symmetry, if that is its necessary nature. Things do not escape from the universe. If I reach my arm out through the edge of the universe, I just create more spacetime through my emanations. Or space wraps back, boundless but not infinite.
If the universe came from something else, we’d just have to go on to that, so let us say that we are already discussing the basic something. To avoid creating something out of nothing, if we have to, it is then a necessity that the basic something has always existed, that is, it is timeless, or eternal, in time, and it is the same as the universe, as it only changed its form, although we wonder why and how. This becomes a problem., as there is still the ‘problem’ of there being nothing to make anything of, and we can’t leave any problems hanging about.
Since the universe is expanding, it cannot be infinite, nor can anything, so it is finite, although perhaps unbounded, which is both by its expansion and if spacetime is curved. Technically, it expands into itself, but it is still not surrounded by anything. The universe’s size and location is relative to nothing, whatever than means and implies.
Only in the expression as the universe from the All of the Something Forever do we have space, time, and the rather enduring amount of finite substance that may even be still growing, as is space, to be classified as finite or infinite (imagine how crowded that would be), but the All is still the All, which means there isn’t any more, so in that respect it is the ‘mostest’ that can be our universe.
We live in the finite but seemingly unbounded and closed universe that constantly changes but is itself kind of future-eternal, as it is only a change, even if in a dispersed form, and it is all of itself, contained to itself, and not really contained by not having anything outside it, for that is a ‘nothing’ which is not there, although this is still called nonexistence, and it ever cannot do anything, anyway, so who cares. Remember, if necessary, we have skipped onwards to that something which is the basis of the universe, in case there were further somethings in-between, such as maybe what gave rise to fields, if that was an intermediate.