Bloodwych

I’m sitting, drinking beer - and then I see All coming! Hello!

Help me get through the subject!
I’ve reached God knows what level - there’s a large hall, its side
wall is “imaginary” and behind it are two “portals” (I don’t know what else to call them) one seems to be red, and the other blue.
In the middle of the hall, in the ceiling, there’s a hole, but there are no stairs:(
In general, I don’t know how to get out of there!