The Walking Dead comic book series has ended, which means the TV show only has roughly two years' worth of material left to adapt. Robert Kirkman's decision to abruptly end The Walking Dead graphic novels has surprised fans, but it's also left them wondering just what it means for the TV series.
AMC has moved to reassure fans by saying that the ending of the comics won't affect their plans for the show, but it will have to have some impact. Although The Walking Dead has long played fast-and-loose with its source material, it has always been there as a rough guideline, which is especially true of big events like the introduction of Negan or The Fair (which was adapted towards the end of season 9). Even if The Walking Dead plans on going beyond the comics, this ending means that there's not much left for it to draw from as inspiration.
Based on where things ended in season 9, and where they're looking likely to go in season 10 and beyond, then we can say that The Walking Dead has around two years of comic book stories left to adapt. Season 9 ended on the precipice of battle against the Whisperers, which is something that should play out next year. That means adapting the comic book storylines "Call To Arms" (issues 151-156) and then "The Whisperer War" (issues 157-162). The Whisperers can be the primary antagonists throughout season 10, although it's unlikely they'd be able to stretch the storyline out beyond that (especially after a similar move backfired in seasons 7 & 8 with "All Out War").
At the same time as it's telling those stories, The Walking Dead will also be continuing to tease the introduction of the Commonwealth. It already started doing this with the radio signals in season 9, but it can become more overt in season 10. The Commonwealth, led by a woman called Pamela Milton, is a vast group of survivors, with the name covering a network of towns made up of around 50,000 people. It's been strongly suggested that this is the community Maggie and her son left for during the six-year time gap following from Rick's supposed death, while it's also been theorized that it could be where Rick was taken to in the helicopter, linking the TV shows even more directly to the forthcoming Walking Dead movies.
The Commonwealth isn't a villain in the same sense as the Saviors or the Whisperers. It's presented, especially at first, as largely decent people, but it just so happens that they've rebuilt society as it was before the apocalypse, which means including things like a class system and inequality. Over time, that does then lead to Pamela becoming an antagonist in the comics, which will presumably play out on the show too in a fashion (it's possible that Georgie, who formed part of Maggie's storyline, will take on that role). Given that The Walking Dead is already setting up the Commonwealth, however, then there's a good chance we'll actually see it before season 10 is over (it's the kind of thing they'd do in a season finale). That would then leave season 11 to adapt the Commonwealth storyline from the comics, which runs for 20 issues. That's enough for just one season of 16 episodes, especially since a lot of it is setup that could be condensed down, and some of the biggest moments involve Rick himself, which now can't happen unless he does return or it's used in the films. That takes us to Issue #193, which is where Kirkman decided to end things.
Of course, there are some major differences between The Walking Dead TV show and comics, with big characters like Carl no longer alive in the adaptation, which will have an impact on how this plays out. The Rick Grimes movie trilogy, too, will have a bearing on things, especially if that's going to be taking elements of the Commonwealth. But it all adds up to the TV show being able to adapt comic book material in seasons 10 & 11, and then being out in its own. It's previously been said that The Walking Dead will run until season 12, and this loosely fits with that: two years left of comics, and then a final season to deliver its own ending.