Is the guy that plays Bryce the same guy that played Jay on the show Traveler? And do you think his character is really dead?

yes and yes unfortunately

On the preview for this weeks episode it shows Bryce is alive. Do you think he will get back together with Sarah?

If not,he'll just put the moves on her and as Chuck walks away from seeing them kiss,she'll push him away and slap him.Something like that.

What I don't get is they called Bryce Chuck's nemesis when they are friends since they had their own language and that's what some friends do.

That is hard to understand. I guess their friendship became strained in college. But still from strained to nemesis is a big jump.