Ok :> the manga is called Ness’ Great Adventure.
There’s quite a couple differences in the story, the ones seen in this chapter being that King’s name is now Mueller, you get to see Paula, Jeff, and Poo even before they are introduced, and that in the later chapters King (or Mueller, should I say) stays with Ness much longer, almost having the same relationship with him as Rush in the old Megaman mangas.