Find sheet music for pieces that sound like they'd be easy. Learn A LOT of pieces like this, maybe buy an adult beginner book and try playing through it.
One of the best ways to keep something down is through repetition (but not monotonous repetition). So, if you start by playing through half page or one page pieces that are not actually that tough for you technique-wise, you'll start seeing the similarities between the staff notation and the keys on the keyboard. Playing one very difficult piece will get you no where.
Print a page or two of scales, and as you play them, look how the notes are moving up and down the staff. Name them as you play them (aloud or in your head); learn a few basic chords to see how multiple notes stack, and what they look like on paper vs. what they look like on the piano.
If you are able to play the Moonlight (I'm guessing the first movement), some of the Chopin and To a Wild Rose, then you have some pretty decent coordination. Use this, go back a few steps, and pick some stuff that you think you can learn without spending a year cranking out one note by one note.