const text = `{
  "hello": "world",
  "numbers": [1, 2, 3]
}`;
const data = JSON.parse(text);
console.log(data.hello);
console.log(data.numbers.length);
const obj = {
  hello: "world",
  numbers: [1, 2, 3],
};
const json = JSON.stringify(obj);
console.log(json);
// {"hello":"world","numbers":[1,2,3]}
const json2 = JSON.stringify(obj, null, 2);
console.log(json2);
// {
//   "hello": "world",
//   "numbers": [
//     1,
//     2,
//     3
//   ]
// }