You can download a report in WhatsApp that contains all the information about your account and what WhatsApp has saved about you. This report is now available on request. Where to download the report in WhatsApp from an iPhone or Android smartphone is explained here:
- First open WhatsApp on your phone
- Tap on the icon with the three dots in the upper right corner and select Settings
- Account → Request account info
- Select "Request report" here. The process can take up to 3 days, depending on the size of the report request and how much information about you is stored on WhatsApp.
You now know how to download the report to your own account in WhatsApp.