Sending mail using asp.net

using send grid also you can send mail , go through bellow link 
https://sendgrid.com/docs/for-developers/sending-email/v3-csharp-code-example/
Create account and generate api key start to use 

code starts form here , any doubt ping me 

// using SendGrid's C# Library 

// https://github.com/sendgrid/sendgrid-csharp 

using SendGrid; 

using SendGrid.Helpers.Mail;

 using System; 

using System.Threading.Tasks;

  namespace Example 

{     

internal class Example   

  {    

private static void Main()

   {        Execute().Wait(); 

   }   

  static async Task Execute()

  {  

  var apiKey = Environment.GetEnvironmentVariable("NAME_OF_THE_ENVIRONMENT_VARIABLE_FOR_YOUR_SENDGRID_KEY");             

 var client = new SendGridClient(apiKey); 

 var from = new EmailAddress("[email protected]", "Example User");

 var subject = "Sending with SendGrid is Fun"; 

 var to = new EmailAddress("[email protected]", "Example User");

 var plainTextContent = "and easy to do anywhere, even with C#";

 var htmlContent = "and easy to do anywhere, even with C#";

 var msg = MailHelper.CreateSingleEmail(from, to, subject, plainTextContent, htmlContent); 

 var response = await client.SendEmailAsync(msg);    

     } 

    } 

}