Legends of Luke Skywalker explores the myths surrounding Luke. The book is set on a ship traveling to Canto Bight, and crew members swap stories of their experiences or encounters with Luke. One story, for example, comes from a droid that details Luke leading a droid rebellion, while another comes from a former Imperial officer that details how the legend of Luke is a complete myth.
This novel does not add much to the actual canon story of Luke, but, instead, takes a more whimsical approach to help convey the reputation that Luke has gained in the Star Wars universe. It was published as part of the Journey to the Last Jedi series and helps to expand upon the larger-than-life character that is Luke before the movie that details the end of his story. It is a fun and easy read!