Unable to delete kernel malware extension.

Create an OS installer drive How to create a bootable macOS Mojave installer drive I strongly recommend you do this from another Mac to be safe. You also want to make a full backup of your stuff as you’ll need to wipe the drive. I would strongly recommend using TimeMachine so you can recover your account, apps & data

Booting up under the created OS installer USB drive run Disk Utility and wipe the drive and then re-install the OS using a new user account (brand new name). Before you more forward make sure apply all of the OS updates and then install a good antivirus/malware app and its updates as you’ll need to check your TimeMachine backup drive as it maybe infected before you run Migration Assistant to bring your user account, apps & data back.

Don’t forget to test your drive again and also check your other external drives.

Now that you have a second user account (the new one) keep it ing make sure you use it to maintain your system Vs your old account. User your old account for your day to day stuff. Make sure the password for this new account is strong as you don’t want it exposed and you should redo your old user account and all of your other account passwords as well.