I need easy recipes and food that reheats well

My grandparents have been married just over 51 years. My grandma took care of my grandpa every day of his life and always made sure he had things to eat. She passed away very suddenly on Wednesday (walked into the hospital Monday afternoon and died Wednesday morning). My papaw has at most a vague idea of how to feed himself but makes some delicious Southwest potato bake-thing. That and box cake are all I know that he knows how to cook.

So, I need either food that I can cook for him to reheat or easy recipes for him to make for himself. I have a week before I have to go back to school and would like to make his life as stress-free as possible. Any suggestions are very much appreciated!