Boruto: Naruto Next Generations' anime may currently be celebrating the 20th Anniversary of Masashi Kishimoto's franchise with a nostalgic time travel arc, but the manga has been in the middle of a pretty intense arc as Jigen and the members of Kara have tried to take Kawaki back from Naruto's protection. Chapter 38 of the series kicked this arc into high gear with a battle between Jigen, Naruto, and Sasuke, and left off with an ominous cliffhanger as Naruto was sealed in a giant coffin in Jigen's other dimension. But not all hope is lost quite yet.
Chapter 39 of the series gives an update on how Naruto is doing, and while we don't actually get to see him, his chakra is still active and confirms that Naruto -- while gravely injured -- is still alive within Jigen's other dimension.
Chapter 39 of the series focuses on the immediate fallout of the battle with Jigen as Kawaki is suspected of leading Kara to the Hokage. With Naruto gone, Shikamaru is doing his best to track down the missing Hokage and is probing Kawaki for any information he might be hiding on the matter. This has led to a conflicting series of emotions for Kawaki, as he's frustrated that his Karma was used to take the Hokage away and he doesn't quite know how to handle his paternal feelings for him.
But there's a hope in that Kawaki's prosthetic arm begins to glow with Naruto's chakra. This arm was a bit emblematic in that in literally and metaphorically connects Naruto and Kawaki together, and one of the caveats of it was that it would always operate as long as Naruto was pumping chakra through it. Kawaki's doesn't have his own, so seeing the arm activate again was a pretty huge victory in of itself.
Seeing the arm functioning once more after it briefly deactivated, Kawaki concludes that Naruto is alive. He was most likely knocked unconscious following the fight with Jigen, and Kawaki can sense him through a chakra link the two share. Now with this connection guiding him, Kawaki, Boruto, Sarada, and Mitsuki have headed to this other dimension and now find themselves face to face with a new member of Kara. One that's just as troubling as Jigen, so although Naruto is alive, it's going to be tough to get him back without a fight.
Originally created by Masashi Kishimoto for Shueisha's Weekly Shonen Jump in 1999, Naruto follows a young ninja, with a sealed demon within him, that wishes to become the leader of his home village. The series ran for 700 chapters overall, and was adapted into an anime series by Studio Pierrot and Aniplex that ran from 2002 to 2017. The series was popular enough to warrant a sequel, Boruto: Naruto Next Generations which is set several years after the events of the original Naruto story and features the children of many of its key characters such as Naruto and Hinata.