7th edition of the Publication Manual of the American Psychological Association came out in 2019. As you look for example citations, etc., be sure that you are looking at recent guides.
Why cite? To show that you've researched your topic; to give credit to the researchers who's work you use to develop your ideas; to avoid plagiarism (i.e. claiming credit for work that is not your own).
Roberts Library. (2020, April 21). Adding a hanging indent in Word for APA or MLA citation page. [Video file]. YouTube. https://www.youtube.com/watch?v=XV31llfb1V4