I know with Google books you can upload PDF and epub books. Can you with movie's or is there an app to upload movies into your personal library so you can stream?
There's no functionality for this right now. You could upload to YouTube, although it would probably get taken down for copyright issues, even if you keep it private and for your own use only. You could try uploading to your Google Photos or Google Drive, but this will obviously take up a chunk of your storage allotment.