If you buy a car with a loan, you must buy auto insurance. Consumers have the right to choose insurance companies. As for whether you must buy insurance in the store, it depends on the contract. If the contract signed when the loan is used to buy a car does not clearly stipulate the renewal of insurance in the designated guarantee company, you can't buy commercial insurance in the 4S shop.

However, the current situation is that it has become a hidden rule for the car loan industry for the guarantee company to designate an insurance company for the borrower. During the loan period, the borrower shall not switch to other insurance companies, otherwise it will be a breach of contract. In case of default, the deposit paid by the borrower is non-refundable.

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