What to do right away if a device you use for Cornell work is lost or stolen: report to the police (Cornell Police for on-campus or any Cornell-owned device; local police where it went missing), change your NetID password, and report the incident (JCB IT handles the ITSO report for Cornell-owned devices; report personal devices yourself).
How to recognize a phishing or suspicious email, report it with the built-in Report button in Outlook (or forward to itsecurity@cornell.edu), and what to do if you already clicked or entered your NetID. Thin JCB wrapper linking Cornell's public it.cornell.edu security pages.