How to completely rid machine of kerberos

My MacBook was also hacked recently. I talked to Apple about it who couldn’t care less and didn’t believe me, saying it sounded like magic. This person has scripts installed to notify them of all downloads, usb inputs, credit card numbers, is in all my email accounts, tracking my devices, gets forwarding of my messages and emails, and so much more. I did a factory format and reinstall which did nothing because of the snapshot and VM installed on my hard drive. What’s worse is he also hacked my friends network too all because I hooked up to wifi there. I know they got in through Kerberos, are using FreeBSD software, and that they use Pam auth. But they are also superuser. I would think Apple would want to get something like this under control with all the ads claiming to be privacy centered. This is simply untrue. I lost an incredible amount already and now how many others will? It seemed so easy for this to happen. This person is tied into my iCloud and tracking my every move and there’s nothing I can do because the company that makes my devices won’t help me fix it.