I need id some phones lines

I am not TI.
In my office I have several phone lines. I have each number to each customer, that is that I want. but I need to identify the line which is entering the call. that mean the phone number which the customer is calling.
How ca I do this.
What I will need.


that should be happening in your extensions.conf file you should be matching the number that the customer dialed in your dialplan to route the call accordingly… or are you wanting to route the call based on the number they are calling from…