You can delete any lines in the usual way. Forward copies an incoming mail with quote marks so it can be sent to someone else. File allows you to move the current email to another folder. Next shows the next unread message in the list. When this appears grey there is no following message.
Print prints a copy of the current message on an attached printer.
Delete removes the current message and places it in the Trash folder. Stop disconnects the mail page from the Internet. Use this if you change your mind about getting or sending mail in mid-session. No mail will be lost. The top main window on the right shows a list of messages in the current folder.