1. Whilst in the inbox click the cog in the top right corner and from the dropdown menu choose ‘More email settings’.
2. Under ‘Customising Outlook’ choose ‘Rules for sorting new messages’.
3. Click new rule.
4. For Step 1: choose subject > is > ‘example subject’ and Step 2 defaults to ‘move to inbox’ or you can choose a specific folder.
I’ve taken screenshots of it as well.