https://partners.viber.com/account/create-bot-account
Node.JS Bot API => https://developers.viber.com/docs/api/nodejs-bot-api/
Python Bot API => https://developers.viber.com/docs/api/python-bot-api/
REST Bot API => https://developers.viber.com/docs/api/rest-bot-api/
Java Bot API => https://developers.viber.com/docs/api/java-bot-api/
Create a file config.php in php directory and add below text
<?php $access_token = 'Your Viber Access Token Add Here'; ?>