If you are paraphrasing an idea from another work, you only have to make reference to the author and year of publication in your in-text reference, but APA guidelines encourage you to also provide the page number (although it is not required.)
Examples:
According to Jones (1998), APA style is a difficult citation format for first-time learners.
APA style is a difficult citation format for first-time learners (Jones, 1998, p. 199).