For the first part of the question- I would clarify that the Egyptian New Kingdom didn’t collapse during the larger Bronze Age Collapse that affected the wider region. Although it was severely weakened and beset by many economic challenges caused by war with Nubia in the south and Libya to the west, alongside other external factors historians debate as the causes of the larger collapse of other societies in the Levant.

Secondly, Egyptian Civilization evolved through many epochs (Old, Middle, New Kingdoms as well as intermediate and late periods) before conquest by foreign empires such as that of Alexander the Great, which takes us to Ptolemaic Egypt (so named after Alexander the Great’s general, Ptolemy who seized the Egyptian crown after the death of Alexander). That is to say that while you can trace a cultural and historical through line from New Kingdom Egypt to Ptolemaic Egypt, Egyptian civilization as understood in the popular imagination had changed quite dramatically by the time the Romans seized political control of Egypt in 30 BC.

The last thing to dispel is that the pharaoh was abolished by the Romans in 30 BC as the title was assumed by the Roman Emperor and only abolished in 314 AD. And so it’s not quite clear when you can mark an exact date for the end of Pharonic Egypt as the last native Pharoah to rule was 343 BC. It would be more accurate to say that the cultural, religious, linguistic traditions and political institutions of Pharonic Egypt gave way to forces such as Christianity, Roman rule and eventually Arab Conquest in later centuries.

Sources:

Spalinger, Anthony John. War In Ancient Egypt: The New Kingdom. Malden, MA: Blackwell Pub., 2005.

Cline, Eric H. (2014). 1177 B.C.: The Year Civilization Collapsed. Princeton, New Jersey: Princeton University Press.

Ian Shaw, The Oxford History of Ancient Egypt, Oxford University Press 2000