As of today, September 21, 2023, there is no officially announced plan for an Iron Man 4 movie. However, there have been rumours and speculation that the film is in development, and Robert Downey Jr. has expressed interest in returning to the role of Tony Stark.
Marvel Studios president Kevin Feige has said that the studio is always looking for ways to bring back popular characters, but he has not specifically mentioned Iron Man 4.
If an Iron Man 4 movie were to be made, it is unclear what the story would be. Tony Stark died at the end of Avengers: Endgame, so the film would need to find a way to bring him back or introduce a new Iron Man character.
It is also unclear who would direct or write the film. Jon Favreau, who directed the first two Iron Man movies, has said that he is not interested in returning to the franchise.
Overall, it is too early to say for sure whether or not an Iron Man 4 movie will be made. However, the rumours and speculation suggest that it is a possibility. Fans of the franchise will need to stay tuned for more information.