I think he is yet to convince himself that he is fully fit before he gets up and move. Just keep trying your best to encourage him, he will walk.
Dad wants to live only to eat and even the doctors finally surrendered by allowing him to eat normal diet instead of patient diet, because he refused to eat them...
That's really strange. Doing the opposite could harm him but I think that's what he feels his body system wants.
Yes, I know, he will not do by himself, so will have to find alternatives.