I am looking to remotely transfer a file from my Linux machine to a Windows machine. I have done some research and it appears that scp is what I want to use to achieve this. However... all of the code that I'm seeing appears to be using cygwin (or similar) that is already installed on the windows machine, hardly "remote." My two systems are completely separate and have their own unique IP addresses.
Filezilla or WinSCP will do the job. It's required only to have SSH server running on your Linux machine, enabled SSH port (tcp/22 by default) in firewall and your Windows computer must be able to reach the Linux host - you can try ping <Linux-machine-IP> from your Windows computer to verify.
If you want something else, you could configure Samba or probably WebDAV (httpd.apache.org/docs/2.4/mod/mod_dav.html), which allow you to mount your Linux directories as drives in Windows without additional tools. For example, your linux home /home/user can be mounted as Y: drive in Windows.