Find this mod in villages!

Bounty boards can be found throughout the world in villages, and they’ll generate bounties inside of them. These bounties often ask for you to bring back an item, or kill some mobs in return for whatever rewards they’re offering. If you can complete the bounty, you just have to bring it back to the bounty board and right click the board to redeem your rewards!
There exists another item as well, called a Decree. A Decree determines what kind of bounties show up on a bounty board. For example, an Armorsmithing Decree makes it so that objectives and rewards related to armor show up on the board (leather, iron, chestplates, boots, etc). You can have up to three decrees on a bounty board at once, and it will mix and match objectives and rewards from all three when new bounties appear!

You can find new Decrees as rewards for certain bounties, or they can be traded with villagers at higher villager levels.