How to uninstall NordVPN from my MacBook with macOS Sonoma?

How to uninstall NordVPN software says,

Uninstall NordVPN from macOS

If you need to completely remove NordVPN from your Mac, Apple has an always-up-to-date article on how to uninstall software on MacOS.

... which is decidedly unhelpful. Then,

 If you need help, do not hesitate to contact our support team.

... which isn't much better.

Since "NordVPN" appears to be disinterested in supporting their customers, I suggest using EtreCheck. For a brief description and instructions, read How to use the Add Text Feature When Posting Large Amounts of Text, i.e. an Etrecheck Report - Apple Community. It is likely to identify the components that cause the product to load upon rebooting.

After trashing the NordVPN app, I still could not load remote content privately on my mac mail app. until I searched the Library for contains Nordlynx and nord and four files came up.

Deleted them and mail works again.

I got a little help from them on removing a file Nord.fs.kext, so they do sometimes help. It took a week or so for a reply.

Here is their instructions.

1. Shut down or Restart machine;
2. Press & hold cmd+R and then see Apple logo release it (for M1 hold power button);
3. When loads Recovery Mode, go to Utility -> Terminal;
4. Run command "csrutil disable" - get a message "system integrity protection disabled, restart computer";
5. Restart into normal mode;
6. Run Terminal;
7. Run command "sudo sqlite3 /var/db/SystemPolicyConfiguration/KextPolicy";
8. Run command "DELETE FROM kext_policy WHERE bundle_id='com.nordlocker.nordfs.filesystems.nordfs';";
9. Repeat steps: 1 -> 2 -> 3;
10. Run command "csrutil enable";
11. Restart into normal mode.

Use Find Any File from the App store and slowly and methodically uninstall the remnant's of the app that the Trash doesn't take out and uninstall apps can't find.