You can find the answer to this in chapter 11 of Frankenstein, in which Victor Frankenstein's creation, generally known as the Creature, begins to tell the story of his own existence and how he has experienced life from the moment of his strange creation.
The Creature says that he felt unable to distinguish between different sensations when he first became aware of himself. He remembers darkness and also that he was confused by the "multiplicity" of sensations that assailed him when he first became aware of his reawakened and reconstituted body.
The Creature describes his early awakening very much in terms of having been brought out of darkness. While at first, he was aware of very little, awareness slowly grows on him in the form of light which becomes acceptable to his eyes. After a time, he becomes able to open his eyes and perceive this light properly.
The Creature does not say anything about having any understanding of where the various parts of his body have come from—in fact, he is unaware of how hideous his own corporation is until he sees it reflected, at which point he is disgusted. At first, he is unable to see very well, but after a while, his vision becomes clearer and the darkness begins to dissipate for him.