Yes, very likely a scam.
iCloud renews automatically, unless you actually cancel it and does not send renewal emails.
Any iCloud account related emails are sent to the attached email address for the Apple Account, if its arriving to an email address that you know is not attached to an Apple account then its also a sign that its a scam.
You can verify an existing iCloud subscription on your Apple account by following the steps in the support document linked below.
click here ➜ Downgrade or cancel your iCloud+ plan - Apple Support
For more info see the following support document.
click here ➜ Recognize and avoid social engineering schemes including phishing messages, phony support calls, and other scams - Apple Support
and here ➜ Identify legitimate emails from the App Store or iTunes Store - Apple Support
You can forward the suspect emails to apple at reportphishing@apple.com