Hi Minny, so very sorry that you find your self in this situation with your dad. I know nothing about final stage care for PCa sufferers but my mother passed away with lung cancer in a hospice and although you know the end is near I tried to get as much " time" with her as I could, with every memory being stored.
Stay strong for your dad you are a wonderful caring daughter and I know you will do whatever you can to make his last period of this crap disease as good as you can.
My thoughts are with you at this time.
Life seems different upside down, take another viewpoint