First of all, please open the Virtual Line configuration board. If you forgot or do not know how to access to it, please follow this link. 

How to open the Virtual Line configuration board?

Below guidance is for scenario of Call Flow with Ring Group

Step 1: Set Welcome Message 

Then, you can follow this link for setup a Welcome Message to sound more professional and create a Extension offer to guide your Caller reach the right person.  

Virtual Line - Set up Welcome Message

Step 2: Create the group of numbers to receive the calls

Virtual Line - How to transfer call to number(s)

Step 3: Record Missed calls and notify

Virtual Line - How to setup a Missed Call Notification?