"Crazy Cattle Ranch" is a breeding game. You need to keep an eye on the condition of the cows, they will be hungry and sick. Only healthy cows can produce milk. After obtaining milk you can exchange it into forage with new cows. You can also use milk to unlock new cow stalls when your cow stalls are not enough.
Milk is obtained by raising cows, which can be exchanged for fodder and new cows.