My MacBook Air has been hacked

Please read About those "<app> will damage your computer" messages - Apple Community.

Won’t let me connect to the internet.

Check System Preferences > Network, and remove any proxy servers: Change Wi-Fi preferences on Mac - Apple Support.

Sorry, the linked conversation wasn't very clear.

You need to delete two launch files. First, boot into Safe Mode. Follow the directions for an Intel or Apple silicon based Mac. Whichever one you have.

The reason for this is if you remove the files while booted normally, at lot of adware will repeatedly check to see if the launch items have been removed. If so, it will create them again and you'll get nowhere.

Once in safe mode. Remove these two files.

/Library/LaunchDaemons/com.AssistiveRecordd.plist

~/Library/LaunchAgents/com.AssistiveRecord.service.plist

The first plist file is in the main Library folder. That's the one you see next to the Applications and Users folders. The second Library folder is in your user account. That's what the tilde ~ represents. You can get there by first clicking anywhere on the desktop, then hold the Option key down and choose Go > Library from the top menu bar.

After putting those two plist files in the trash, delete them and then restart normally. Unless the adware has changed since that post and other files need to be removed, or the file names have changed, that should do it.

A file was inadvertently downloaded from the internet and it cannot be done without you physically choosing to download it. It was most likely represented to be something else, such as a "Flash Player Update", or a scan to speed up your computer, or a scan to remove a fake virus. The article referred by John Galt will be able to solve your problem with the message you are seeing.

It's adware you inadvertently installed. See this previous topic:

Macbook Air - Apple Community