An international call can be dialed through a VoIP phone the same way it is dialed through any landline phone.
In most cases (depending in the VoIP provider’s software), a leading ‘+’ can be used in the call sequence (replacing the international exit code).
|+ or exit code||one to three digits||phone number|
|dialed to reach the international switchboard||destination country code||local phone number in the destination country|
Which country or region am I calling from?
When you dial a call from a VoIP phone, you are always dialing the call based on where the phone number is registered.
If a caller is using a VoIP phone service registered to an American phone number, and is currently accessing the service while in physically in France, the call is placed as if the caller was physically in the United States.
Even if that caller was placing a call to a local French phone number, it would still be placed as a call from the United States.