根据数组索引获取嵌套文档

{
  "_id": ObjectId("60a1e1e6a9e1c3f7e8a2f7a1"),
  "name": "John",
  "age": 30,
  "hobbies": [
    {
      "name": "reading",
      "level": "advanced"
    },
    {
      "name": "gaming",
      "level": "intermediate"
    }
  ]
}

db.collection.find({ "_id": ObjectId("60a1e1e6a9e1c3f7e8a2f7a1") }, { "hobbies.0": 1 })

{
  "_id": ObjectId("60a1e1e6a9e1c3f7e8a2f7a1"),
  "hobbies": [
    {
      "name": "reading",
      "level": "advanced"
    }
  ]
}