Huh I dont get it, he bit him soo does that mean they're bonded forever??

Lmao exactly

It depends on the authors. Each author pretty much tweak omegaverse to how they want it. I've actually read quite a lot of omegaverse that has a temp bite mark bond, plus some worlds have bond breaking and such.
I'm guessing this author has temp biting bond and permanent biting bond? But we'll see!