We learn a lot more from the questions we get wrong than from the questions we get right. Don't let it get you down. In this case occupation is similar to the English, and means something that occupies you, so it could mean "he finishes the job/task". It could also mean the end of an occupation of e.g a country. I put "he quits the job", but this is wrong because you wouldn't say it this way in Portuguese - "deixa/termina o trabalho/emprego" is far more likely. You might hear "deixou a ocupação" used to mean "he left the profession". I'm not a native speaker so others please correct me if I'm wrong!