If you're using Windows and you want to use a video that's been encoded using ProRes, you have to install a decoder. You can't Encode to ProRes on Windows, but you can still use stuff that uses the codec.
If you TRANSCODE it into a visually lossless format to work with that isn't quite as humongous as Animation at full quality, use Avid's DNxHD. It's free to download, it works on Mac and Windows, and it's great. It's not as great as ProRes, but it's still excellent.