Reprocess Raw is available in Photos, if you installed a system update, that changed the raw processing. Photos will not automatically reprocess the RAW files after a RAW update, because it may change the look of a photo. You can do it manually, after you installed an update, but can skip it, f you like the current look of your photo. Use Raw as Original is only available for RW+JPEG pairs, as OT explained.
The File Type badges "R" and "J" are only shown for RAW+JPEG pairs as well. If you imported a pair, you will see the R badge, aid the RAW component is the original and the J, if the JPEG is the original. With only RAWs imported, these badges are missing.