You can manage your e-mails with rules, eg. an automatic reply or a SPAM rule, or to forward your e-mails.
When you enable rules, they will be continuously applied.

Enable an automatic reply (vacation message)

Forward or divert e-mails

You can forward your mails to a different e-mail address.
Forwarded messages will be shown as messages that were sent by you. Replies will be sent to the address that forwarded the message and not to the original sender.

Set a SPAM rule