Should I use FTP or SFTP command?

I set up a FTP server using these instructions: https://www.windowscentral.com/how-set-and-manage-ftp-server-windows-10

If I wanted to SECURELY upload files to this server via CMD (Command Prompt), should I use the FTP command or SFTP command in CMD? What's the difference between the 2?

If I want to be more secured and protected, do I need to do anything else?

Please advise. Thanks!

FTP (like http) is unencrypted. FTPS adds encryption (like https).

The walkthrough you linked to is for ftp, and specifically turns security (SSL) off, so even if you can connect via ftps it still wont be encrypted - which means any party between you and the server can intercept the traffic (and get your password).

In order to secure your connection you would need to change to ftps and require a cert. An alternative is to set up a VPN server on your ftp server and then connect to ftp across the VPN. Another solution would be to drop ftp and implement ssh (sftp or scp) transfers.