Chapter 574 is titled “Portgas D. Ace Dies”.

What episode did Ace die?

“Looking for the Answer – Fire Fist Ace Dies on the Battlefield” is the 483rd episode of the One Piece anime.

Which volume did Ace die?

One Piece, Vol. 59: The Death of Portgaz D. Ace (One Piece Graphic Novel) Kindle & comiXology.

Ace visited Wano Country for years before the current storyline, where he met Otama. Ace promised to come back to Wano Country and free it one day by defeating Yonko Kaido but unfortunately, he died before accomplishing this goal.