Short answers, pulled from the story.
The 1991 Star Wars video game was released for the Nintendo Entertainment System in North America in November 1991, the Family Computer in Japan on the 15th of November 1991, and in Europe on the 26th of March 1992. Game Boy, Game Gear, and Sega Master System versions followed in 1992 and 1993.
The Game Boy port was developed by NMS Software and published by Capcom, released in 1992, less than a year after the original NES version.
The Game Gear version includes exclusive levels, including one in which Leia delivers the stolen Death Star plans to R2-D2. The Tatooine hub world is replaced by three side-scrolling on-foot desert levels, and players must kill and resurrect Han Solo or Princess Leia to earn the final ten percent of completion points.
Darth Vader appears only on the Game Over screen in the 1991 Star Wars NES game, making no appearance during regular gameplay.
On the 28th of June 2019, Limited Run Games re-released the NES and Game Boy versions as unlicensed replica game cartridges in limited quantities, available in both standard and Collector's Edition sets.
An NES adaptation of Return of the Jedi was planned but never completed. The series continued with Star Wars: The Empire Strikes Back in 1992 and a Super NES counterpart called Super Star Wars, also released in 1992.