Short answers, pulled from the story.
George Lucas created Lando Calrissian in 1978 as a gambler foil to Han Solo with elegance similar to James Bond. Lucas initially envisioned him as a genetically manipulated clone from a ruling clan to make Princess Leia distrust him immediately.
Billy Dee Williams portrayed Lando Calrissian in The Empire Strikes Back which was released on the 1st of May 1980. He reprised the role in Return of the Jedi released on the 25th of April 1983 and appeared in The Rise of Skywalker released on the 24th of December 2019.
The Aurebesh text on Lando's cane reads Baron Lando Calrissian but fans translated it as Landonis Balthazar Calrissian III. Writers of The Rise of Skywalker confirmed that Landonis Balthazar Calrissian III is his full name.
L. Neil Smith wrote the trilogy of science fiction novels chronicleing Lando's smuggling days before the original trilogy. The first novel Lando Calrissian and the Mindharp of Sharu was published on the 1st of July 1983 followed by two other books later that year.
Billy Dee Williams publicly admitted in 2015 that he received backlash from children who were angered by Lando's betrayal of Han in The Empire Strikes Back. He felt the situation would have been different if Lando had been played by a white actor because of racial dynamics in the story.