Cyber Diplomacy Act of 2021 This bill establishes requirements related to diplomatic engagement with foreign countries on matters of U.S. cyberspace policy. Specifically, the bill establishes the Bureau of International Cyberspace Policy within the Department of State to advise the State Department on cyberspace issues and lead diplomatic efforts on issues related to international cybersecurity, internet access and freedom, and international cyber threats. The bureau must undertake specified duties and responsibilities to implement the stated U.S. policy of working internationally to promote an open, interoperable, and secure internet governed by a multi-stakeholder model that (1) promotes human rights, democracy, and rule of law; and (2) respects privacy and guards against deception, fraud, and theft. The President must devise a strategy for U.S. engagement with foreign governments on international norms related to responsible state behavior in cyberspace. Further, the President is encouraged to enter into executive arrangements with foreign governments that support U.S. cyberspace policy. In addition, annual country reports on human rights practices must include assessments of freedom of expression in each country with respect to electronic information, and the Government Accountability Office must report on U.S. diplomatic processes and other efforts with foreign countries to advance U.S. interests in cyberspace.