is there a way to track my stolen iphone if it has been turned off

No, sorry. ALL of the following must be true to track a lost iPhone.

1. The phone must be powered on
2. The phone must be connected to a network
3. Find My must have been enabled before the phone went missing.

See this about what to do if your phone is lost or stolen --> If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support

No there isn’t … BUT …

Mark it as “lost,” set a message, and request a notification when found.

You’ll at least get a notification when (if) it comes back “on net” and be able to quickly assess if it’s possibly “coming back” … or not.

Edit to add: Be VERY cautious of e-mails or texts purporting to be from Apple re: your phone.

This is a too common scam to gain entry into your phone … or worse; access into your iCloud account.