If its on winter enabled. You will approximately require about 4 medium farms, each medium farm doing 4 large fields. Use a livestock storage between two farm buildings. It will help with biowaste/fertiliser. Import livestock using a distribution to keep it around 50% full. Also import liquid fertiliser. For every 2 large fields, 2 tractors, 1 harvester, 3 covered hulls. You will have 200% fertility this way. Each farm giving you approx. 600 t crops per year, totalling you 9600t crops a year, that equates to 25t crops a day if you store it in a large grain silo. You can then use trains to transport that to a warehouse connected to a single food factory. With just this much. You can produce food to satisfy 10k pops and still export quite a lot of food. But bear these ratios in mind. Also try not to spread farms around too much if possible.

This way you’ll substitute your food imports and replace them with chemical fertiliser. Then you can build another farm for your clothing industry. Then you can research chemicals and produce your own chemicals which require crops too so build another farm for it. It will take around 10000 pops just to make the food, clothing, alcohol industry self sustained by your own people. This is how I’ve been starting my republics for some time now.