Federal System Incident Response Act of 2020 This bill requires federal agencies to notify impacted individuals following major or significant cybersecurity incidents, or incidents determined to have involved sensitive personal information. Each agency must make available information relating to an incident to the Cybersecurity and Infrastructure Security Agency (CISA), the Department of Defense, and the Office of Management and Budget (OMB) to help mitigate future incidents. CISA shall perform continuous monitoring of incidents of federal information systems and produce an annual report. OMB shall develop guidance on what constitutes a major incident. Each agency must develop training on how to identify and respond to an incident.