using System;

using System.Text.Json.Nodes;

​

public class Program

{

    public static void Main()

    {

string jsonString =

            @"{

  ""Date"": ""2019-08-01T00:00:00"",

  ""Temperature"": 25,

  ""Summary"": ""Hot"",

  ""DatesAvailable"": [

    ""2019-08-01T00:00:00"",

    ""2019-08-02T00:00:00""

  ],

  ""TemperatureRanges"": {

      ""Cold"": {

          ""High"": 20,

          ""Low"": -10

      },

      ""Hot"": {

          ""High"": 60,

          ""Low"": 20

      }

  }

}

";

        JsonNode jDataSet = JsonNode.Parse(jsonString)!;

        var dataSet = jDataSet.AsObject();

        foreach (var entry in dataSet)

        {

            if (entry.Key == "TemperatureRanges")

            {

                entry.Value.AsObject().Remove("Hot");

            }

            else if (entry.Key == "Date")

            {

                dataSet.Remove(entry.Key);

            }

        }

    }

}