WhatsApp rolls out the “Proxy” connectivity function to users, which is how the app can be used if it is blocked within a country.
WhatsApp does not offer Proxy servers itself, leaving the server preparation function to volunteers and institutions around the world. What WhatsApp has provided is connect via Proxy within its application.

connect via Proxy maintains WhatsApp’s level of privacy and protection. Your personal messages will continue to be protected by end-to-end encryption between the parties – ensuring that they remain between you and the person you communicate with and do not appear to anyone else or on Proxy servers. The data shared with Proxy servers is the user’s IP address.

You can access the option from the following:

1- From the app interface open the menu
2. Choose Settings
3. Storage & Data > Proxy.