Q: my son has misplaced or had his ipod stolen but when i ring his facetime its ringing?would this happen if its been stolen?because it must be connect to a wifi. thank you

"would this happen if its been stolen?"

it could happen if it has been stolen.  The thief can be connected to wi-fi.

The fact that it is ringing gives no information about its current disposition.

If the FIndMyiPod feature was already turned on in Settings>iCloud then go to iCloud and then sign in and go to FindMyiPhone. You may be able to find its general location.

iCloud: Troubleshooting Find My iPhone, iPad, iPod touch, or Mac

If wifi is on and the iPod is automatically set connect to available networks then it will connect.