In my opinion, Naruto Uzumaki will not be killed maybe he will be pushed to a near death state and then a miracle is going to save him and plot armor is always there for help. Also, the people in Japan do not like to watch main characters die and if Naruto is to be killed it might reduce a lot of fanbase of Boruto Anime.
Now, is Sasuke Uchiha dead or not in future? In my opinion a big no to that as well. Well, that’s simply because we are talking about the two most powerful beings on the face of Earth. If Kaguya, Madara, Nagato and his six paths of pain and Obito could not stop them no way in hell it makes sense that some cocky newbie will kill them. I’m sharing all this without even getting into the details of the superpowers.