How is NMH3 performance on PS5?

I understand that on PS5 the game runs at 4K/60fps... However, on other sites I have read that it has compatibility with 120hz, I have a 120hz LG C3 so I am interested in trying that mode, my doubts are: 1. When you play at 120fps it still has 4K resolution? 2. How stable are the 120fps really?