How do i scan Chrome hacked with fake Apple warnings on MacBook Air?

To scan your Mac for malware, download and run the Malwarebytes utility application.  The app was designed solely to seek out adware and known malware and remove it. It’s a popular tool among veteran users here in the Community. Run the app and see if it can identify any malware you may have accidentally installed. The free version is probably all you need at this point to identify and quarantine potential problems.  Remove what is found from the quarantine.

Malwarebytes Anti-Malware for Mac

Malwarebytes Uninstaller

Also, you can turn off these bogus notifications from Chrome by going to System Settings > Notifications. Scroll the list to find the Chrome app and then disable the app from sending notifications.

Notifications settings on Mac - Apple Support

If these things are appearing in the upper right hand corner of the screen, they may be Web notifications.

This User Tip shows how to block them for Safari.

Stop unwanted Notifications - Apple Community

The idea is the same for any other browser (Firefox, Brave, Chrome, …) that you are using, although the details of where the controls are located would be different.