noun, の adjective
The employment members of a workplace are the personnel or staff. Pretty straightforward!
職員 and 社員 are two similar terms, but have different meanings. 社員 generally refers to employees of private companies, while 職員 refers to employees who work in various fields such as civil service, education, government, non-profits, and more.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
I’m not a teacher, but I am part of the school staff.