It is possible to record by:

• Despite the fact that WhatsApp does not allow users to record calls, there is a acmethod by which users can record any call. You'll need to utilise a third-party software to record your WhatsApp calls. Both Android and iOS users can use this approach to record calls.
• If you have an Android phone, you will need to utilise a third-party app to record your calls.
•  You can use your phone to download the cube call recorder or any other app.
• Now go to WhatsApp and launch the app
•  Make the call you want to save a recording of.
• Know that your call is being recorded if you see cube call widgets in the app.
• If you receive an error message on your phone, you must reopen the app.
• Go to the app's settings and select Force Voice in Voice Call.

Read More: How would you improve WhatsApp?