TLDR: Ryan Gosling will be going on a perilous mission that may change and alter the future of the Force.

New Details Regarding the Movie’s Direction
A newly surfaced synopsis for Star Wars: Starfighter on IMDb has revealed fresh details about the upcoming film’s story.
According to the description, Ryan Gosling’s character will become involved in a dangerous mission that could potentially reshape the future of the Force itself.
The synopsis describes the story as follows: “a solitary pilot” in a rebuilding galaxy who becomes entangled in a critical mission as new threats begin to emerge.
The journey is said to carry major consequences for the future of the Force.
Post-Sequel Era Setting After The Rise of Skywalker
The film is set five years after the events of The Rise of Skywalker, moving the Star Wars timeline into largely unexplored territory on screen.
Gosling will reportedly play a lone pilot navigating a galaxy still recovering from the aftermath of the sequel trilogy.