Before his reappearance in the second season of The Mandalorian, the last we saw of Boba Fett was his alleged death on Tatooine. Given that The Book of Boba Fett was introduced at the end of the season two finale of The Mandalorian with Boba Fett entering the castle of the deceased Jabba the Hutt and executing Bib Fortuna before taking Jabba’s throne, The Book of Boba Fett will surely explore Tatooine.
The place of Jabba’s base of operations is, of course, also known as the planet where a young Anakin Skywalker grew up as a slave before being taken away to train as a Jedi, where Obi-Wan waited in exile after the fall of the Republic and the execution of the Jedi, and where Luke Skywalker, under the watchful eye of Obi-Wan Kenobi, grew up with his uncle Owen and aunt Beru.
As we learned in The Mandalorian, Boba Fett lived there for several years after surviving the Sarlacc and losing his armor, which was later found by a sheriff by the name of Cobb Vanth. Tatooine almost feels like the center of the Star Wars universe at times, and it will surely play a prominent role in The Book of Boba Fett.