WITH
T AS (   SELECT CAST(CONCAT ('$', IIF(TRY_CAST([Key] AS int) IS NOT NULL, CONCAT ('[', [Key], ']'), '.' + [Key])) AS nvarchar(MAX)) AS Path
              , [Key]
              , Value
              , Type
              , 1                                                                                                                   Lvl
         FROM OPENJSON (@json_doc)
         UNION ALL
         SELECT CAST(CONCAT (T.Path, IIF(TRY_CAST(O.[Key] AS int) IS NOT NULL, CONCAT ('[', O.[Key], ']'), '.' + O.[Key])) AS nvarchar(MAX))
              , O.[Key]
              , O.Value
              , O.Type
              , T.Lvl + 1
         FROM T
             CROSS APPLY OPENJSON (T.Value) O
         WHERE T.Type IN ( 4, 5 ))
SELECT Path, T.[Key], T.Value, T.Type, T.Lvl FROM T;