How to remove malware from my MacBook Pro?

As etresoft wrote it's not malware. However, in light of macOS's obsession with operating system security it might as well be, hence the somewhat misleading dialog box. "Misleading" in that it's likely to cause alarm, leading to inappropriate actions that can easily result in real problems.

I understand that particular problem is now gone, but given the additional troubles you appear to be experiencing his program EtreCheck is likely to provide information that will help others identify what's ailing your Mac.

To use it please read Using EtreCheck - Apple Community. Instructions for posting its report in a reply to this Discussion are included in that User Tip. It is also available on the Mac App Store: ‎EtreCheck on the Mac App Store.

Either one is ok; your choice of one or another or none of the above. Posting its report is likely to help determine what's wrong with Farcebook.

There is no evidence of malware in that report. Any dialogs or pop-up boxes characterizing HP software as malware are misleading, as others already noted.

Uninstall the "Norton" / "Symantec" product according to its instructions.

Battery failure - Your battery is reporting that it needs to be serviced.

Get that fixed: Mac Service and Repair - Official Apple Support. A battery in need of service is no longer capable of providing the power a Mac needs to run at peak efficiency when needed. The result is slow performance that manifests when particularly demanding tasks are performed. "Facebook" is probably an example of a resource-intensive task but I don't use it so I wouldn't know.

Click here and run the tool.

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That's not malware. It was just a screw-up at Hewlett Packard.

You don’t have to pay for anything. You don’t have any malware. It was just a big accident.

You do not need to pay for it. The free version will suffice. Just post its report in a reply to this Discussion. Instructions for doing that are included in that User Tip.