Originally Posted by
Ultimate Captain America
Question 1: the black Nick Fury.
Two decades ago, Marvel reinvented most of its characters in the Ultimate Marvel universe. Nick Fury was reimagined in "The Ultimates", with the likeness of Samuel Jackson. It was one of the best received reimaginations, even 616-Fury used it as a "disguise" a time he was undercover. Then the real-life Samuel Jackson played the part in the MCU films, and now that's the default aspect of Nick Fury for audiences everywhere. Even animated series and videogames use it if they include him. We still had the problem that Ultimate Marvel was an alternate universe, so they created "Nick Fury Jr." to have him around. And to avoid having two, they retired the original one (more about it later). Ultimate Marvel ended during Secret Wars, but Ultimate Nick was not rescued from it like Miles Morales and the Maker because 616 already had him, in a way. So, that's the guy.
SHIELD was closed after Secret Empire, and then we did not see very often. There's little to do with a guy defined by SHIELD if SHIELD is out of the picture. He has been in an Iron Man annual, Daughters of the Dragon, Invisible Woman, Fantastic Four, Black Cat, and a dispute with Nighthawk in a comic whose name I forgot.
Question 2: the white Nick Fury.
The original one had a long life because he used the "infinite formula" or something like that (super soldier serum under another name), but it was running out. For reasons I forgot (the plot was a bit convoluted) he killed Uatu the Watcher, and the other Watchers sentenced him to be "The Unseen". Basically, a Watcher himself, chained to the Moon. In some times he did the Uatu thing of "I see everything but can not interfere".
When Empyre ended (a between humans, Kree and Skrulls against the Cotati) he took a pair of Cotati weapons, to study them, and Uatu came back to life. He did not simply release him: he recruited him as his agent. Things ended in disaster during the Reckoning War, a war between the Watchers and the Reckoning. The Moon itself was destroyed, but Uatu (who is now more like Eternity) rebuilt it at the end. Along with his former home and everything within, which is now for Fury to use as he see fit.
Fury is now "The Man on the Wall", someone who takes covert action against threats to Earth from outer space. This means... don't be surprised if he appears in this new Secret Invasion. It's his job. I would ask for his resignation if he doesn't!