Every reference I have seen says People of Praise.
“Correction: This article’s headline originally stated that People of Praise inspired ‘The Handmaid’s Tale’. The book’s author, Margaret Atwood, has never specifically mentioned the group as being the inspiration for her work. A New Yorker profile of the author from 2017 mentions a newspaper clipping as part of her research for the book of a different charismatic Catholic group, People of Hope. Newsweek regrets the error.”
People of Praise has no connection to the book.