Can someone hack my account with my debit card?

Where are you seeing this charge?

If the only evidence of this charge is an email make certain the email is actually from Apple. Read here for how to identify legitimate Apple Emails: Identify legitimate emails from the App Store or iTunes Store - Apple Support

You can log in to https://reportaproblem.aplpe.com to verify any and all charges made on your account within the last 90 days and raise an issue with them as well as request a refund.

Also read here: Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams - Apple Support

Follow the steps here to access your entire purchase history: If you see 'itunes.com/bill' or an unfamiliar charge on your statement - Apple Support

How do you know there was a person on your account? What exactly happened that made you think this?

Does the person have a Chinese or "foreign" name? If so, earlier this year there was a security issue about this which apparently Apple knows about and on which they are working (https://discussions.apple.com/thread/8347621?answerId=33272624022#33272624022). You may find you must contact Apple Security to leave the Family Group. https://discussions.apple.com/thread/8360297?answerId=33321712022#33321712022

Somebody may have determined your Apple ID password and is connecting you to their Family Sharing so they can download anything you purchase. You need to:

Change your Apple ID password https://support.apple.com/HT201355

Leave Family Sharing - http://support.apple.com/HT201081

Set up two factor authentication:

Two-factor authentication for Apple ID - https://support.apple.com/HT204915 - "Two-factor authentication is an extra layer of security for your Apple ID designed to ensure that you're the only person who can access your account, even if someone knows your password." Uses a "trusted" device to receive a passcode to verify adding a device.

In general:

If you think your Apple ID has been compromised - https://support.apple.com/HT204145

If you have problems such as not being able to leave the Family Group:

Contact Apple for help with Apple ID account security - https://support.apple.com/HT204169 "This article provides country-specific Apple Support contact information for customers seeking help with their Apple ID password or other security-related issues."