Just applied for the position of hotel personnel assistant, and was asked to go to the market to do research on the day of training. Is this normal? Is this the job of a personnel assistant?

When you say normal, do you mean normal work or normal hotel operation? If your hotel is a legally operated enterprise, no matter what tasks the enterprise and superiors give you, it is normal and legitimate. If you don't understand, you should ask for advice and study diligently. Knowing the cause and effect of why there is such a job content is also a kind of growth.