In the movie she has left earth, gained superpowers at some point, and is now part of a Kree special forces unit called Starforce
In this shot of her team you might notice Ronan the accuser and Korvath (
the "Who?!?" guy from Guardians) presumably before they became evil, as Korvath at least is on the team.
Jude Law plays Mar-Vell, her mentor. Lee Pace reprises his role as Ronan.
The movie covers the Kree-Skrull war, a major event from the comics. These are the Skrulls, a shapeshifting race adept at infiltrating other civilizations before conquering them. Ben Mendelsohn plays their leader, clearly infiltrating Earth in this scene.
It takes place in the 90s so expect to see plenty of 90s fashion, plus it's got a digitally de-aged Sam Jackson as Nick Fury prior to his promotion to director (and prior to losing an eye).
Danvers' origin is as an air force pilot. The movie also features another fighter pilot Maria "Photon" Rambeau as a side character, who is clearly meant to be a nod to
Monica Rambeau, another character who has donned the Captain Marvel moniker who has also gone by various other names including Photon. Maria is likely meant to be Monica's mother, which since this is set in the 90s could be setting up a future MCU character for phase 4.