Tag clound in Element List

Elastic Stack Kibana
1

I have a document that contains a list formatted as a dictionary.

How can I extract the first element or the value of an element by its key to create a tag cloud?

{
  "document_id": 1,
  "terms": [
    {
      "key": "apple",
      "value": 10
    },
    {
      "key": "banana",
      "value": 5
    },
    {
      "key": "cherry",
      "value": 7
    }
  ]
}