If you want to generate your email bodies in razor, you can use Mailzory. Also, you can download the nuget package from here.
// template path
var viewPath = Path.Combine("Views/Emails", "hello.cshtml");
// read the content of template and pass it to the Email constructor
var template = File.ReadAllText(viewPath);
var email = new Email(template);
// set ViewBag properties
email.ViewBag.Name = "Johnny";
email.ViewBag.Content = "Mailzory Is Funny";
// send email
var task = email.SendAsync("mailzory@outlook.com", "subject");
task.Wait()