Lost new Iphone

There is nothing you can do except to file a police report in the country the phone was stolen. Apple NEVER gets involved in lost or stolen items. They are in the business to sell things, not track down things which are stolen. Since you never had the opportunity to activate the phone, you have no way of finding the phone.

Did Turkish customs confiscate the phone and give your friend a confiscation receipt? You could use that to file a police compliant or claim your phone back from customs. If Customs confiscated it because of breach of duty, there is nothing you can do about it as customs tend to auction or sell confiscated phones

Someone stole the phone and, if it was not activated by you previously, they activated it. You need to make a police report. There is nothing we or Apple can do - sorry.

Apple cannot and will not do that. They are not in the investigations of stolen goods business. You need to do that using the find my app and also file a police report. Ask the police to investigate.

If it was never activated, then you cannot use find my. All you can do is report to police.