baseItem.json and workerClothesShirt.json

baseItem.json
{
  "parent":"builtin/generated",
  "display": {
    "thirdperson": {
      "rotation": [ -90, 0, 0 ],
      "translation": [ 0, 1, -3 ],
      "scale": [ 0.55, 0.55, 0.55 ]
    },
    "firstperson": {
      "rotation": [ 0, -135, 25 ],
      "translation": [ 0, 4, 2 ],
      "scale": [ 1.7, 1.7, 1.7 ]
    }
  }
}

workerClothesShirt.json
{
  "parent":"prisonconstructor:item/baseItem",
  "textures": {
    "layer0":"prisonconstructor:items/workerShirt"
  }
}