What is the difference between personal online shop paying social security and unit paying?

If your online shop is a registered enterprise, it is the same as the company.

If it is a person, it may be different. Many places pay social security to individuals according to the proportion of flexible employees. In other words, you can only participate in endowment insurance and medical insurance, but you may not be able to participate in work-related injuries, maternity and unemployment.

The specific situation is subject to the local social security reply.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.