Practically speaking, even during the worst part of the Dust Bowl, when tens of thousands of family farms were wiped out, those farmers outside of the disaster area produced more food than the country could eat. People were hungry only because it was more expensive to haul it to where they lived than what it was worth.
Right now, the US grows equal amounts of corn and soy, about 72.7 million acres worth. 53 million acres of wheat in about 42-46 of the states. And 3 million acres of rice.
About 40% of the US corn crop is wasted on ethanol.
There are 5 million or so empty houses in the US, that with water and power turned on would be quickly habitable, not counting people who could double up (likely family) with under-utilized houses, like a single person who lives in a three bedroom house.
Medical care is a different matter. The vast majority of medical care is preventative and routine. If that is discontinued, vast healthcare resources are freed up for actual problems. Of course they would be a recognition that a lot of treatable diseases today would be left untreated.
The Feds also pay farmers not to grow crops.