we have an URL which contains the JSON data, now I am trying to use JSON.Net to read it.

step1: set up

1. create a website in visual studio and right click the Solution Explorer panel on the left, select Manage NuGet Package...
2. notice to switch Package source to All or nuget.org and then Browse "Newtonsoft.Json" and install
   Ref: https://docs.microsoft.com/en-us/nuget/tools/package-manager-ui

step2: create model

add a .cs file as a container, name it corresponding to the JSON object in that URL. There are many ways to auto generate the attributes from that URL, one way is go to this website: http://json2csharp.com/#;
Another way is copy the JSON file then go the the model.cs file, click Edit button on the top of VisualStudio click Specialpaste - paste JSON as Classes, my model is like this:

FoodNearbyModel.cs

public class FoodNearbyModel
{
    public string API_Status { get; set; }
    public string AdminRemarks { get; set; }
    public string Category { get; set; }
    public string ContactEmail { get; set; }
    public string ContactInfo { get; set; }
    public string ContactNumber { get; set; }
    public string ContactStatus { get; set; }
    public float Distance { get; set; }
    public string EatBookArticle { get; set; }
    public string EntryAddress { get; set; }
    public string EntryDescription { get; set; }
    public int EntryID { get; set; }
    public string EntryName { get; set; }
    public string FacebookPage { get; set; }
    public string Instagram { get; set; }
    public float Latitude { get; set; }
    public float Longitude { get; set; }
    public string MasterCategory { get; set; }
    public string OpeningHours { get; set; }
    public string PostalCode { get; set; }
    public string SubFilter { get; set; }
    public string TSLArticle { get; set; }
    public string TSLReviews { get; set; }
    public string Website { get; set; }
    public string Zone { get; set; }
}

step3: create JSonParser

add another .cs file name as JSonParser

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Net;
using Newtonsoft.Json;

public class JSonParser
{
    const string url = "https://appsbytsl.com/API/V1/Nearby/Food/H4D3S/1.319190/103.857834/3";
    static List<FoodNearbyModel> foodNearby;
    
    //public JSonParser()
    //{
    //    string json = new WebClient().DownloadString(url);
    //    foodNearby = JsonConvert.DeserializeObject<List<FoodNearbyModel>>(json);
    //}

    public static void initialise()
    {
        string json = new WebClient().DownloadString(url);
        foodNearby = JsonConvert.DeserializeObject<List<FoodNearbyModel>>(json);
    }
    public static List<FoodNearbyModel>GetAll()
    {
        initialise();
        return foodNearby;
    }
    public static List<string> GetByCategory()
    {
        initialise();
        return foodNearby.Select(x => x.Category).Distinct().ToList();
    }
}

step4: call JSonParse in webForm

using System;

public partial class DefaultPage : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        GridView1.DataSource = JSonParser.GetAll();
        GridView1.DataBind();
    }
}