index.js

let data = {
    "name": "Servipag Escuela Agricola",
    "online": false,
    "location": {
      "region_id": 13,
      "region": "Metropolitana de Santiago",
      "office": "servipag-escuela-agricola",
      "district": "Macul",
      "country": "Chile",
      "city": "Santiago"
    },
    "category": "servipag",
    "lines": {
      "servipag-escuela-agricola-cheque-deposito": {
        "waiting": 8,
        "name": "Cheque Depósito",
        "elapsed": 245.76666666666668
      },
      "servipag-escuela-agricola-atencion-general": {
        "waiting": 21,
        "wait": 197,
        "name": "Atención General",
        "elapsed": 341.53164556962014
      }
    }
  }
Object.entries(data.lines).forEach(([key, val]) => {
  console.log(key); // the name of the current key.
  console.log(val); // the value of the current key, in this case an object
});