Okay so there’s two Hooks in that scene a present Hook and a future Hook that’s already gone through HH’s post curse and he’s traveling back to the past to be reunited with Emma. He and present Hook get into a fight and FH is asking all these questions because Emma dies in his timeline and FH warns present Hook of that and how Emma needs to leave otherwise her and the baby will die. So then the timeline is corrected. FH is reunited with Emma and they live HEA with their baby. Present Hook goes to HH’s and we all know what happens post curse. Present Hook becomes Future Hook essentially.
It’s basically like the scene in 3×21 the same Hook but in two different points in his life.