Professor Charles Xavier has been the leader of the X-Men for years now, training young mutants to master their powers all while advocating for mutants rights in the public sphere. One of the most recognizable aspects of Professor X's character is his wheelchair—he is one of the few characters in comic books that is visibly disabled. Or rather, he was visibly disabled, since the current version of Professor X can walk just fine. But this isn't the first time Professor X has found himself no longer needing a wheelchair to move. In fact Professor X has a long history of being temporarily given the power to walk again.
Professor X has been cured of his paralysis multiple times in X-Men history, but every time so far it's been undone. The story of how Xavier was originally paralyzed was first told in X-Men #20 where Professor X recounts his battle with an alien called Lucifer in the Himalayas. During the fight Lucifer managed to crush Xavier's legs with a boulder, forcing him to use a wheelchair. Xavier's legs were later healed in Uncanny X-Men #167 when the spacefaring Starjammers used their technology to repair his body after a battle with the alien Brood, beginning one of the longest stretches in continuity where Xavier could walk.
Years later Professor X would suffer another injury in battle depriving him of the ability to walk, this time while fighting the Shadow King on the astral plane in Uncanny X-Men #280. Xavier was back in the wheelchair yet again, but he was temporarily healed in Uncanny X-Men #297 by Apocalypse, albeit for a single day. Charles wouldn't gain the ability to walk for real until Grant Morrison and Frank Quitely's New X-Men, where Xavier's spine was healed by the mutant Xorn. Or at least that's what everyone thought had happened, until Xorn was revealed to be Magneto in disguise and the newly villainous Magneto broke Xavier's legs yet again. A retcon later established that this was not the real Magneto, but Xavier's legs remained broken.
After being relegated to the wheelchair yet again Xavier would later be cured in Deadly Genesis where his spine was fixed by the Scarlet Witch's reality warping magic from House of M. Xavier was able to walk from that point on until his death in Avengers vs. X-Men in 2012. After briefly being trapped on the Astral plane Xavier's mind was then transplanted into the body of Fantomex, after which he was able to construct a new, younger body for himself with the ability to walk. Following this Xavier and rest of the X-Men relocated to the mutant island of Krakoa in House of X where, thanks to Krakoa's technology, Xavier along with every other Krakoan mutant gained the ability to reincarnate into replacement clone bodies whenever they die.
As long as Krakoa can keep making clones, Professor X won't have to worry about his spine being damaged ever again. But there's no telling how long the current status quo for the X-Men will last, and if Krakoa does fall apart there'll be nothing stopping future writers from putting Charles back in the wheelchair. Charles Xavier has been paralyzed and cured multiple times in the comics but for now the leader of the X-Men should be able to walk for the foreseeable future.