How do I convert a JSON output to plain text?

I have a JSON output that goes as follows:

{
  "Item 1": "
    "Item 1 description."
  ],
  "Item 2": e
    "Item 2 description."
  ],
  "Item 3":  
    "Item 3 description."
  ]
}

Each item has a column in my Google sheet. I want each item description to end up in its relevant column.

I know I can do the last part via mapping to Google sheet via the Google Sheet action. The part I don’t know is how to convert the JSON to plain text, and then have each item description as line items or items I can map separately. 

Any tips would be appreciated.