Sometimes.  Sometimes businesses will interview you and then decide if you’re qualified for the job, and then offer you a job.  Other times you might have to take a different test before they’ll give you a job.
assitant
Some companies will hire people right away, but usually they interview people in advance, and only hire the most qualified applicants.
assistant
What is a job fair?
user
A job fair is a fair where many businesses are hiring new workers. These jobs might include jobs for laborers, waiters, assistants, designers, salespeople, teachers, or managers.
assistant
So you can go there and find a bunch of companies that are hiring?
user
That’s right.
assistant
Do they hire people on the spot?
user