The best you can do for him is make sure he is healthy as possible going into the surgery. Eating greens, protein (!) and vegetable. Multi vitamin at least. Walking, swimming, or whatever every day! And, most important, find thriving survivor stories. They are out there in many places.

Lastly, remember there is a Great Physician that works through our doctors. Give Him the glory and your trust. It will be okay
If he is already healthy he shouldn’t need you home more than 2 weeks after hospital release. He will be sore but not incapacitated!