A purely spiritual being, such as God, can only be said to be “in a place” to the extent that it ‘acts’ in a place, because it has no physical parts to actually spread out in any space or place.
Because everything that is, exists only by reason of God’s continuing creative will, God is said to be omnipresent by the fact that he holds everything in existence. In that sense, he is at the heart of every thing, holding it in existence. But He does not take up any space.
He is also omnipresent in the sense that there is nothing, anywhere in the universe, of which he is not aware.
(He also, of course, holds the angels in existence, but they are also spiritual beings.)