CCAvenue test and production environments are separate.

Merchants need to have an Active CCAvenue accout to use any of the the environment. The Test environment doesn’t process any payment.

Here are the URLS

CCAvenue Test URL:     https://test.ccavenue.com
CCAvenue Production URL:    https://secure.ccavenue.com

From Settings tab > API Keys page; copy the following credentials:

Merchant ID   
Access Code
Encryption Key

visit https://www.paymentgatewayintegrationhelp.com/CCAvenue/CCAvenue-Payment-Gateway-integration-Help-Initiate-Transact-9132.asp to know how to integrate.