There are books on this sort of things, the topic is vast. From energy supply to commercial food operations, there are a lot of very different situations. This

There are books on this sort of things, the topic is vast. From energy supply to commercial food operations, there are a lot of very different situations. This said, I reckon that all-out cyberwar on the scale necessary to impact food supply, would see IRL retaliation too quickly for it to matter. The US military has its own network strategy, its own satellites, etc etc, so they will be ready to pounce.