Selco, Since he is a war veteran he knows how to defend him self with weapons and has some ideas on security. He is missing is food and water storage knowledge.
Start him on the cheaper foods first and build up from there. Have him start by storing rice and beans. Then add can foods that can be added to the rice and beans. Then after that he can start other foods(grains, pastas, can foods, etc).
On water you will have to show him the ways to filter water and were to find and store water.
This will be a start. I think that you need to go slow since if you go to fast he will feel like it is to much.