this is arok reincarnation right.....next story will be klop reincarnation..?

Yeap

then can i ask why klop having a dream of hes first life is he a reincarnated also in arok 2nd life..? or just a dream for him

You could say it's a dream, the book didn't explain about it. Maybe it's his subconsciousness or somewhat the world turns back the time with only Aeroc as the only one with memories. But klop in the second story is not the klop in first story.