If you would like to Send an email message, click on the New Message button near the top left within Outlook.
Make sure you fill out the To field with the email address of the person you want to receive your email, then create a subject and type your message in the white space below.
All of your received emails will go in your Inbox. You may choose to Reply to an email if you would like to respond to the sender.
After opening the email message, just click on the reply button near the top right of the received email. You can also press the reply all button if you would like to respond to everyone who was included in the message.