For every in-text citation that you include in your assignment, you need to have a corresponding full citation on the References page. Similarly, every citation entry on your References page should represent at least one in-text citation. It is easiest to collect the full citation information for every resource that you find while doing your research, then drop the ones that you use into the References page as you use information from them in your narrative, as it can be very challenging if you wait to build your full citations while writing your paper!
Visit Purdue's OWL to see a sample APA paper including a References page; another example to help you visualize the format for a References page is shown here in a graphic by Jennifer Betts of Bibliography.com (2021):
A full citation for the References page of an APA work will include 4 basic elements separated with periods: Author. (Date). Title. Source. For additional information, the APA also a concise guide for full citations of journal articles, books, and book chapters, as well as an extensive list of example reference citations for various circumstances.
American Psychological Association. (2020). Publication manual of the American Psychological Association: The official guide to APA style (7th edition).
Betts, J. (2021, March 17). APA Citation Generator (Free) & Complete APA Format Guide. Bibliography.com. https://www.bibliography.com/apa/apa-format-and-citations/
Purdue OWL. (n.d.). APA Sample Paper. Purdue Writing Lab. https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/apa_sample_paper.html