The last time we saw the red-haired assassin, she was sacrificing her life for the Avengers' mission in Avengers: Endgame, so you're probably confused about where Black Widow fits in the grand scheme of the Marvel Cinematic Universe. Simply put, the film is a prequel that takes place before Natasha's unfortunate demise. So no, unless Marvel Studios decides to pull a very unexpected switcheroo, Black Widow won't feature Natasha's resurrection.
The film takes place after the events of Captain America: Civil War and before Avengers: Infinity War. Fans will recall that Civil War ended in the chasm between Tony Stark and Steve Rogers, as well as the Natasha "betraying" Tony to help Steve escape. The next time we see her, she's with Steve and Sam Wilson in Infinity War, sporting some serious blond locks. The Black Widow trailer reveals that Natasha's actions made her an enemy of the government, which drives her into exile. The standalone film will show what she was up to before she returned to in Infinity War.
Fans will meet Natasha's "family" from her time as a Russian-trained assassin. We'll learn more about Natasha's mysterious past and, hopefully, understand more about the hero. Black Widow will premiere worldwide on May 1, 2020, and we. Can't. Wait.