During the battle, Nick Fury and Black Widow made it look like the severely injured Bucky actually died, both to push Rogers back into the role of Captain America and also allow Barnes to restart his life. In treating him, they injected him with Fury's last vial of Infinity Formula.

Does Bucky Barnes die in endgame?

The Steve Rogers of Avengers: Endgame knows all too well what happened to his best friend Bucky Barnes after World War II. Bucky didn't die when he fell off that train. Instead, he became the brainwashed HYDRA assassin known as the Winter Soldier.

Does Bucky Barnes die in Falcon and the Winter Soldier?

But the possibility is definitely there. As you probably know, there was a moment where Bucky had died, but he actually was saved and then transformed into the Winter Soldier by the Soviet Union and HYDRA — where he was given a bionic arm — and was then used to commit assassinations all over the world.