From: Turn on automatic forwarding in Outlook - Microsoft Support
You can automatically forward or redirect your email messages by setting up Inbox rules. This is useful if you want to read and respond to messages from another email account or when you want someone else to receive and respond to your email in your absence.
At the top of the page, select Settings .
Select Mail > Forwarding.
Select Enable forwarding, enter the forwarding email address, and select Save.
Note: If you want a copy of the original message to remain in your mailbox, select Keep a copy of forwarded messages.