TL;DR Marvel's meta-cosmology consists of six stacked realms, each transcending the previous one: The Neutral Zone (Malkuth), The Far Shore, The Beyond (Yesod), The White-Hot Room (Tiferet), Da'at and The House of Ideas (Kether). The relationship between them is as follows:
House of Ideas = The realm of pure oneness where only The One Above All exists, transcending all else. It is from here that infinite stories are born, but they are still only ideas, and have to go through several stages before they can become a world.
Da'at = The realm containing all possibility and impossibility. Here, God starts to consider ways in which his creation could be, as well as the ones in which it could not be.
White Hot-Room = The realm of the fires of creation, which forge the possibilities of Da'at into actuality. Here, God says "Let there be light," and the surge of energy that follows is the Big Bang thet gives birth to the cosmos.
Beyond = The foundation on which the world to come will rest. Here, the creative energies produced in the White-Hot Room are harnessed and start being organized and solidified into something concrete. Whereas the White-Hot Room precedes the birth of form, Yesod is the place in which the shape of creation is sketched out, beginning to exist in idea, but not in actuality.
The Far Shore = The pathway between The Neutral Zone and the Beyond, above space, time, life, death and self.
The Neutral Zone = The lowest world. The omniverse as a whole.
So, long story short, The One Above All is 8 levels above baseline High 1-A. There are infinite layers of emanation above them, and a nebulous, unknowable "Godhead" above them all.