android - Update and delete data in Firebase

Question

This is my database:

{
  "UID1" : {
    "KEY" : {
      "Name" : "name1",
      "Email" : "something1@something.com",
      "userid" : "UID1"
    }
  },
  "UID2" : {
    "KEY2" : {
      "Name" : "name1",
      "Email" : "something1@something.com",
      "userid" : "UID2"
    },
    "KEY3" : {
      "Name" : "name2",
      "Email" : "something2@something.com",
      "userid" : "UID2"
    },
    "KEY4" : {
      "Name" : "name3",
      "Email" : "something3@something.com",
      "userid" : "UID2"
  }
}

I would like to update and delete data which for example would be at the position of "KEY2".

How can I achieve this? I have not yet tried any code in Android.

Answer 1

Waitting for answers