Work implies something that's physical--something that requires effort. It is generally short-term. A job is generally long-term. It implies that you do it over a period of time rather than it being a one-off event. It also implies that it's a position of some sort. Unlike a "job," "work" refers to the actual content of your job. Your work is part of your job, but your job cannot be part of your work because work is a piece and a job is a whole (if that makes sense).

Often they are the same. My job is also my work. Sometimes "job" is more formal. You will have to read more to learn when each is used. It is not simple.

Work is rather general. It could be used to describe school work, house work etc as well as employment. Job is often used to describe employment as well as a task or errand. In regards to employment work is more common though. E.g. Where are you going? I'm going to work. What type of work do you do? I work mainly in finance. What do you work as? I work as a bartender. However, job and work are sometimes interchangeable. E.g. I need to find work/ I need to find a job