Like I said, instead of searching Google and Youtube, you should be fixing this as Microsoft says:
"If you're seeing notifications that the copy of Windows that is installed on your PC might not be genuine, or that you might be a victim of counterfeit software, it's likely that your copy of Windows was not properly activated or is otherwise not genuine.
To fix this, click the notification and follow the steps to either repair Windows or—if you have inadvertently obtained counterfeit software—buy genuine Windows.
Until you correct the issue, you'll receive periodic reminders that Windows is not genuine. In addition, to more clearly display these messages, your desktop might turn black...