The tricky part is zz. In Italian a double z between vowels is ts, as in pizza (PEET-sa). So the word is not paparazzi with a z sound. It ends in raht-see (US) or rat-see (UK).
The word is the plural of paparazzo, one photographer. It became famous through a character called Paparazzo in the 1960 Italian film La Dolce Vita, and English picked it up from there. English uses paparazzi as a plural noun.
Cambridge lists the American form with ah vowels and the British form with a, and Oxford has no entry for it. Put the weight on the third syllable and say ts clearly.