With the start of Jujutsu Kaisen’s Shibuya Incident arc, the anime returns to its present-day of 2018 after a series of flashbacks. The Jujutsu Kaisen 0 movie, released between the show's two seasons, follows the events of the year before Yuji arrives at Tokyo Jujutsu High. The Gojo’s Past arc, which encompasses the first five episodes of Season 2, brings the show back to 2006 and Gojo’s high school years. This focus on the characters' histories, with two consecutive flashbacks, raises the question of why Jujutsu Kaisen is so concerned with the past—and what this might say about its future.
Source：https://www.cbr.com/jujutsu-kaisens-past-future-reveals/
