For food at the beginning you’ll want to gather blueberries, roots, and mushrooms (Harvest Wild Food in the Removal Menu). You get a surprising amount of food that way, especially if you keep some of the forest or bog around your village. Those foods cover 3 of the 4 food groups. To get protein you could use 1-2 fishermen or you could hunt for venison. Smoking the fish and meat helps you get more of it.
If you look around the forums I think you can find some recommendations about crop field sizes. But yes, smaller. I’m micromanaging one 9×15 field for a new village with 30 people. I let 2 workers plant it, then use 5 or 6 to harvest it. In the winter I assign them to something else.
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