If you leave school and start work, but you don't have too many qualifications, you are entitled to reasonable paid time off to study or train for more qualifications while you are aged 16 or 17. Jobs are changing all the time, so no-one really knows what jobs will be available. It's hard to believe, but only 20 years ago there was no such thing as a computer games designer or an aerobics instructor. You might have seen jobs in the job file that you'd be great at and you might have a good idea what you want to do. But by the time you leave school, or college or university, there'll probably be other new jobs which haven't even been thought of yet.
Many people think that in the future people are less likely to spend all their lives in one job.
People will progress from one job to another, or change from one career to another. They're more likely to have periods without work. A lot depends on you, your skills and ambitions. The way we work may also change. And more people will be self-employed.