When referencing a chapter from a book, use the following format for APA 7th edition:
Author, A.A. (Year of publication). Chapter title. In A.A. Editor and B.B. Editor (Eds.), Title of book (pp. xx-xx). Place of Publication: Publisher.
For example, if you are referencing Chapter 5, "Shakespeare's Process," from the book Unlocking Shakespeare's Language by Caroline F. E. Spurgeon (1972), the reference would look like this:
Spurgeon, C.F.E. (1972). Shakespeare's process. In A.L. Rowse (Ed.), Unlocking Shakespeare's language (pp. 83-96). Garden City, NY: Anchor Books.