Secondary sources can often provide leads to primary sources and/or provide background or contextual information that is relevant. Consider trying
In general, there are three types of resources or sources of information: primary, secondary, and tertiary. It is important to understand these types and to know what type is appropriate for your coursework prior to searching for information.
It's sometimes difficult to distinguish among these three types and they do vary by discipline and subject.
Representatives of the Biden administration and the executive branch may appear before Congressional committees to provide information on administration policies, initiatives, etc. or to respond to oversight requests; for example, Secretary Blinken appearing before the House Foreign Affairs Committee on March 10, 2021 to speak on the Biden's administration's priorities for U.S. foreign policy (video available on committee site).
Sources that can be used to search for hearings, witnesses, and testimony include