In Dwarf Fortress
, that most ridiculous of simulation games, they farm, hunt, fish, raise livestock for meat, eggs, milk and cheese, and keep bees. They can also trade. It may well be that all the player needs
to do is to build a couple of underground farms (alcohol is much more important anyway) and set a couple of dwarves to raise different crops. Fortunately, the player base is as crazy as the game.
Underground farms seem to support a small but adequate
number of crops, mostly mushrooms. Open-air crops are more varied, but they're a security risk or a cause for projects like building enclosed glass-roofed valleys. I've only played a short succession game, and there our fortress was built into the back wall of a canyon with strawberry patches in front of the gates. It's also possible to grow underground lumber, like tower-caps and tunnel tube.
Underground rivers are great for fishing. The wiki also discusses building traps on the riverbed, but retrieving the fish requires damming or redirecting the river. It even mentions eating whales, but there are no boats and that probably involves draining parts of the sea. Overground pastures for grazing animals are a hazard, but they can be sent to underground caverns to eat cave moss or floor fungus.
Dwarves may also eat kittens, but that's not crazy, that's a necessity. The furry things can breed like Tribbles and kill the framerate, and once they adopt dwarves as their owners you're pretty much stuck with them.