How does ezio die

Ezio Auditore died peacefully at the age of 65 in his hometown of Florence, Italy after settling down and having 2 children (Marcello and Flavia Auditore). He tutored a young Chinese assassin by the name of Shao Jun in his final years, preparing the next generation for the dangers that the Templars posed.

Also for anyone who wants to watch it, there is a video that is about Ezio's life after the Assassins Creed games involving him. It is called "Assassins Creed: Embers" and can be found on YouTube.