Before you can print a mail from your computer, you first need to install a printer. To print a mail, you can log in to your Email account on the official website, open the mail that you want to print, go to the mail options and choose Print. This can be done in other way by selecting all the text from the mail, copying and pasting it to a Word document and printing it from there.
To print a mail using Outlook, you need to open it first, go to File and choose Print.