O.J. Simpson is reportedly undergoing chemotherapy despite posting a video on Friday in which he appeared to flaunt his good health. News broke earlier in the day that the 76-year-old was diagnosed with prostate cancer, after a report was widely shared from Miami’s ABC affiliate Local10, citing sources close to the matter. Somehow, a rumor seemed to get back to “The Juice” that people thought he was in hospice care, because he then took to X, sharing a video from behind the wheel of his car and telling the camera, “I’m not in any hospice, I don’t know who put that out there.” Simpson didn’t ad…