In the past, the company paid social insurance and changed companies. What procedures or relevant documents do I need to pay for insurance in my current company?

You need to go to the original unit to give you all the information of surrender (pension handbook, social security relationship transfer form, original social security bill), and take these information to the person who handles social security in the current unit to help you handle it. It's all up to you to make up for it. If you want to make up, you can go to the social security bureau to make up, and go to your current unit to apply for insurance. If you don't make it up, you can ask your current unit to renew it for you.