minecraft-assets/data/minecraft/recipes/bone_meal_from_bone_block.json

{
  "type": "minecraft:crafting_shapeless",
  "group": "bonemeal",
  "ingredients": [
    {
      "item": "minecraft:bone_block"
    }
  ],
  "result": {
    "count": 9,
    "item": "minecraft:bone_meal"
  }
}