Dim Json As Object
Set Json = JsonConverter.ParseJson("{""a"":123,""b"":[1,2,3,4],""c"":{""d"":456}}")

' Json("a") -> 123
' Json("b")(2) -> 2
' Json("c")("d") -> 456
Json("c")("e") = 789

Debug.Print JsonConverter.ConvertToJson(Json)
' -> "{"a":123,"b":[1,2,3,4],"c":{"d":456,"e":789}}"

Debug.Print JsonConverter.ConvertToJson(Json, Whitespace:=2)
' -> "{
'       "a": 123,
'       "b": [
'         1,
'         2,
'         3,
'         4
'       ],
'       "c": {
'         "d": 456,
'         "e": 789  
'       }
'     }"

' Advanced example: Read .json file and load into sheet (Windows-only)
' (add reference to Microsoft Scripting Runtime)
' {"values":[{"a":1,"b":2,"c": 3},...]}

Dim FSO As New FileSystemObject
Dim JsonTS As TextStream
Dim JsonText As String
Dim Parsed As Dictionary

' Read .json file
Set JsonTS = FSO.OpenTextFile("example.json", ForReading)
JsonText = JsonTS.ReadAll
JsonTS.Close

' Parse json to Dictionary
' "values" is parsed as Collection
' each item in "values" is parsed as Dictionary
Set Parsed = JsonConverter.ParseJson(JsonText)

' Prepare and write values to sheet
Dim Values As Variant
ReDim Values(Parsed("values").Count, 3)

Dim Value As Dictionary
Dim i As Long

i = 0
For Each Value In Parsed("values")
  Values(i, 0) = Value("a")
  Values(i, 1) = Value("b")
  Values(i, 2) = Value("c")
  i = i + 1
Next Value

Sheets("example").Range(Cells(1, 1), Cells(Parsed("values").Count, 3)) = Values

JsonConverter.JsonOptions.EscapeSolidus = True