Is my iPhone 13 hacked?

You haven't been hacked. It is a scam message designed to get you to purchase unnecessary software or phish for personal information. 

Read more about it here -

Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

You have NOT been hacked. You clicked on a link which is designed to scare you into believing you've been hacked. No one can simply access your phone remotely from a link. They will of course try to get you to pay them to rid yourself of something you don't have.

Ignore and delete the message. Don't provide them anything.

Read this --> Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

Very likely a lie, designed to panic you into clicking a “tech support” link or calling a “tech support” number for “help.”

The people at the other end of the link or phone line would be the criminals who sent the message, waiting for you to deliver yourself hook, line, and sinker into their “tender” hands. Don’t bite, and don’t be a “phish.”

I received the same message," Your iPhone has been hacked," when browsing in Safari today. I immediately deleted the page and turned off my phone.

Three people have given the answer.