internal class Program
    {
        private static void Main(string[] args)
        {
            var urls = new[]
            {
                "https://httpbin.org",
                "https://httpbin.org/get",
                "https://httpbin.org/ip"
            };

            var results = DownloadAsync(urls).Result;

            foreach (var result in results)
            {
                Console.WriteLine(result);
            }
        }

        private static async Task<string[]> DownloadAsync(IEnumerable<string> urls)
        {
            var settings = new ProxySettings
            {
                Host = "127.0.0.1",
                Port = 1080
            };

            using (var client = new HttpClient(new ProxyClientHandler<Socks5>(settings)))
            {
                var tasks = urls.Select(url => client.GetStringAsync(url));

                return await Task.WhenAll(tasks).ConfigureAwait(false);
            }
        }
    }