How to get bounds of streamed levels?

I have a somewhat working procedural generator for my levels I’m trying to figure out how to get the bounds of the tiles(Which are each an individual “level” that is streamed in at runtime.)

I would then use the total area to get both the lengths and widths of the generated rectangle to place collisions on the maps “edge” that would tell it to generate more world when a player crosses it.

Is there a way to get the sum bounds of multiple streamed levels and detect if they are x, x-, or y, and y-?(Relative to 0,0,0 of course.)

From there it would be just placing collisions at runtime when the forloops are done. And then transforming the 4 collisions to match those areas.

Any help appreciated thank you.