Natural Remedies for Prostate Cancer in Husband

My husband has Prostate Cancer, stage 3 or 4, not sure yet. We are seeing a new Urologist next week and hoping he's open to alternative treatment. After watching my 68 year old brother die an excruciating death from the "aggressive treatment for lung cancer" (ie. massive Chemotherapy) my husband has decided against a biopsy and Chemo. The Nuclear medicine bone scan was negative...so we're encouraged. The MRI and PSA tests are what we're going off. He is 83 and was hospitalized in November for a Staph infection which required 4 weeks of IV antibiotics. They also gave him Remdesivir without my knowledge, and he has not bounced back. Any advice on how to proceed and not cave to doctors is appreciated.