>>1072183my dad did the same before he died.
I dont know how financially mobile you are but I ended up buying my dad a seniors with disability fishing permit, a spincast combo (which i still have somewhere in the garage) and basically kidnapped him for a weekend.
I rented a small house boat and rolled his ass on and made him fish. was a total bitch about it at first (muh meds) but eventually slid into fishin and bullshitting mode and had a great time. It was the first time in my life I ever saw him cry. miss that fucker but thats the cycle of life we all will eventually deal with. I think you should try to get him out before it's too late to go. read up on some lakes, look into senior fishing programs in your state, ect.