A job is a particular position or role for which you are employed.
- I have a new job.
- She applied for a job.
- He lost his job.
Work is a broader word for an activity or effort, especially employment.
- I have a lot of work today.
- She goes to work at eight.
- He is looking for work.
Easy guide
You can have a job and do work.
Job = specific position.
Work = activity, employment or tasks.