Email Marketing
Mailchimp: https://mailchimp.com/
Mailerlite: https://www.mailerlite.com/
GetResponse: https://www.getresponse.com/
EngineMailer: https://www.enginemailer.com/
For further learning, you can watch the video: https://airasiaacademy.com/on-demand-learning/email-marketing
Post your email screenshot here