const obj = {
  name: "Quantum",
  regular: function () {
    return this.name;
  },
  arrow: () => {
    return this?.name;
  },
  nested: function () {
    const inner = () => this.name;
    return inner();
  },
};

console.log(obj.regular());
console.log(obj.arrow());
console.log(obj.nested());