I am being billed through Apple.com/Bill, the amount of $8.18. Want to know what this is for.

The most important part of the first article FoxFifth linked is "View your purchase history." If Apple does NOT show a record of the charges in your history, it is very possible that scammers have gained access to your credit card or bank number and are pretending to be Apple. It happened to us.

If that is the case, only your CARD ISSUER or BANK can remedy it.

If Apple’s purchase history shows the purchase, continue with the instructions in that article.

This is primarily a user-to-user support forum; other Apple users like you. We don't have access to information about charges to your account. Apple has a support article about charges — see each of the steps in the following instructions. They include information on contacting Apple Support if the other steps don't help. See: If you see 'apple.com/bill' on your billing statement - Apple Support

or go to Subscriptions and Billing - Official Apple Support