How do I get the information from the iPhone that was taken from me?

Follow this guidance from Apple→If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support

Beware of a common phishing scam: You may get a text or email from “Apple” or “Apple Security” (or sometimes “Police”) saying your phone has been found and to click on a link to see its location. This is NEVER from Apple or from law enforcement; it is from the thief or fence to steal your Apple ID and identity. Delete any such message without responding to it. Apple never gets involved in lost or stolen devices→Avoid phishing emails, fake ‘virus‘ alerts, phony support calls, and other scams

If you have your own iCloud account and you synced your data to it, you should still be able to log into it through your computer and access things like photos, contacts, notes, maybe even files.

If you were sharing an Apple ID and no longer have access to it, you may be out of luck.

Contact the police.