The following resources can help you learn more about Resource Description and Access:
Functional Requirements for Bibliographic Records, Rev. Ed. 2011.
Maxwell, Robert L. Maxwell’s Handbook for RDA. Chicago: ALA, 2014. The best book on RDA.
Oliver, Chris. Introducing RDA: A Guide to the Basics. Chicago: ALA, 2010. An excellent primer, especially on theoretical questions.
RDA Record Examples. Excellent examples of RDA MARC records for a variety of formats.
Stanford—RDA Questions and Answers. Very detailed.
Planet Cataloging. A great collection of cataloging-related blog posts.