I am looking to buy a portable keyboard piano but would prefer to be able to download piano music onto it and learn how to play it. Do they make one that will do this? I'd also like it to have light up keys since I have to go by photographic memory while learning since I can't read sheet music.
They do make something like you describe, but they usually accept MIDI files not typical sheet music. Casio makes a few light up keyboards, and I'm pretty sure the LK-280 can be loaded with MIDI parts and the lights will guide you. Some of them only play the songs that come with the keyboard, so make sure you confirm the model you want will allow you to load files of your own.
In the long run it is very much worth it to learn how to read sheet music. You won't always have a light-up keyboard available, and depending on what genre or style of music you are playing there might not always be MIDI files available for the songs you want. Also learning to read music gives you better glimpse into music theory and where the notes are coming from, rather than just following the lights.