How to breed villagers in Minecraft with a simple breeder
Two villagers, three beds and a small carrot field are enough for a breeder that runs on its own.

The Carrot is both a food and its own seed: plant it on Farmland and it grows into a carrot crop that gives back several carrots. It restores three hunger points and is the favorite food of pigs and rabbits.
It cannot be crafted; it can be found in chests. It can be composted: each one has a 65% chance to add a layer to a Composter.
Fully grown carrots drop up to four carrots, more with Fortune, so a small field quickly feeds itself and you. Villages often have carrot fields, and zombies sometimes drop one.
Holding a carrot makes Pigs and rabbits follow you, and feeding it to two of them makes them breed. Horses, donkeys and mules eat carrots too. On a fishing rod, a carrot becomes a Carrot on a Stick, the tool that steers a saddled pig.
Eight gold nuggets around a carrot make a Golden Carrot, one of the best foods for saturation and the key ingredient of night vision potions. Carrots are also an ingredient of rabbit stew, and a novice Farmer buys them for emeralds.
This item has no crafting recipe.
Two villagers, three beds and a small carrot field are enough for a breeder that runs on its own.
Villages grow Wheat, Carrots, Potatoes and Beetroots.
Each failed try makes it calmer, food speeds things up, and two tamed horses fed Golden Carrots give you a foal.
It can be found as loot in Pillager Outpost and Shipwreck. It is dropped by Husk, Zombie and Zombie Villager. Bought by Villager: Farmer (Novice).
It is food, its own seed, pig and rabbit food, and an ingredient of golden carrots, carrots on a stick and rabbit stew. It is an ingredient in 3 recipes, made at the Crafting Table; for example Carrot on a Stick, Golden Carrot and Rabbit Stew. Animals that eat it: Horse, Donkey, Mule, Pig and Rabbit.
3 hunger points (1.5 drumsticks) and 3.6 saturation.
Yes. Each Carrot put in a Composter has a 65% chance to add a layer (the first layer in an empty Composter always works). After 7 layers the Composter gives Bone Meal.
A Balanced Diet (Eat everything that is edible, even if it's not good for you).