Steps to  know if Your Chromebook was hacked:

• Unwanted Toolbars and Antivirus Messages When unusual antivirus warning messages appear, warning you of a possible threat, the threat is often as good as delivered. ...
• Redirected Internet Searches and Kidnapped Homepages You use Google to look for information about kidnapped homepages and receive results that are completely unrelated to your query. Like the infamous Stuxnet, some viruses or malware will intercept your Internet queries and hide them behind many proxies, preventing you from discovering what's really going on and then deleting themselves.
• Your gadget has been hacked if it wakes up in the middle of the night, texts nonsense, explores menu paths, appears to play poker with itself, and then reads an e-book after the pleasure of poker wears off.
• Because personal information is stored on devices, a hacker could gain access to credit cards, email addresses, and passwords. Update your passwords right away, notify your friends that you've been hacked, and take the procedures necessary to retrieve any accounts that have been shut out.
• They provide hackers access to your device in the same manner that unwanted toolbars do. Consider removing them immediately. You may examine and delete undesirable apps and programmes on almost all devices.

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