How to use Infatica Residential proxy with C#

Using WebRequest
using System;
using System.IO;
using System.Net;

namespace ProxyRequest
{
    class MainClass
    {
        public static void Main(string[] args)
        { # Change the proxy login, password, IP, and port from your proxy list if you use authorization by login/password.
            var myProxy = new WebProxy("http://Host:Port", true);
            myProxy.Credentials = new NetworkCredential("login", "password");

            var request = (HttpWebRequest)WebRequest.Create("http://ip-api.com");
            request.Proxy = myProxy;
            request.PreAuthenticate = true;
            request.AllowAutoRedirect = false;
            request.ServerCertificateValidationCallback += (sender, certificate, chain, sslPolicyErrors) => true;

            var response = request.GetResponse();
            Console.WriteLine("Response Status: " + ((HttpWebResponse)response).StatusDescription);
            Console.WriteLine("\nResponse Headers:\n" + ((HttpWebResponse)response).Headers);
            var dataStream = response.GetResponseStream();
            var reader = new StreamReader(dataStream);
            string responseFromServer = reader.ReadToEnd();
            Console.WriteLine("Response Body:\n" + responseFromServer);
            reader.Close();
            response.Close();
        }
    }
}

Asynchronous Request with HttpClient

using System;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

namespace AsyncProxyRequest
{
    class MainClass
    {
        static void Main(string[] args)
        {
            _ = AsyncMain();
            Console.ReadKey();
        }

        public static async Task AsyncMain()
        {
            string requestUri = "http://ip-api.com";
            string crawleraApiKey = "login:password";
            string crawleraAuth = Convert.ToBase64String(
                Encoding.Default.GetBytes(crawleraApiKey ));
            string crawleraUri = string.Format(
                "{0}:{1}", "IP", "port");

            WebProxy proxy = new WebProxy(crawleraUri, true);
            CookieContainer cookieContainer = new CookieContainer();
            HttpClientHandler httpClientHandler = new HttpClientHandler()
            {
                Proxy = proxy,
                PreAuthenticate = false,
                UseDefaultCredentials = false,
                UseProxy = true,
                UseCookies = true,
                CookieContainer = cookieContainer
            };
            HttpClient client = new HttpClient(httpClientHandler);

            int _TimeoutSec = 300;
            client.Timeout = new TimeSpan(0, 0, _TimeoutSec);
            client.DefaultRequestHeaders.Add("Proxy-Authorization", "Basic " + crawleraAuth);

            try
            {
                HttpResponseMessage response = await client.GetAsync(requestUri);
                HttpContent content = response.Content;
                Console.WriteLine("Response Status Code: " + (int)response.StatusCode);

                string scrapedPage = await content.ReadAsStringAsync();
                Console.WriteLine("Response Content: " + scrapedPage);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }
    }
}