According to the law, both the insured and the insured need to sign by themselves. If the insured is underage, the parents can sign on their behalf.

If it is not signed by me, the contract is invalid according to law.

But according to the process, after purchasing insurance, the insurance company will call back.

On the phone, the other party will confirm with you whether the terms are clear, whether the age is correct, and whether the signature is signed by myself.

If everyone answers yes, the insurance company may acquiesce that you are my signature.

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