an occupation (formal) = työ, ammatti, elinkeino
Please, state your name, address and occupation.
a profession – a type of job that requires special training, e. g. work connected with law, medicine or education = ammatti, ammattikunta
I’m in the legal profession. I’m a lawyer.
work (uncount noun) – the tasks and duties which form your job and which you are paid to do = työ, työt, työnteko
I’m a doctor. I have too much work.
a job – the work a person does regularly to earn money = työ, tehtävä, urakka, työpaikka
I’ve got a good job. I’m a plumber.