@Unicat: There's no "file transfer server" running by default on Windows. You have to enable/install some.
Nowadays, I'd recommend using OpenSSH that's built-in in Windows 10/11 (but the server is not enabled by default).
See Installing SFTP/SSH Server on Windows using OpenSSH.

That's a highly specific thing. I don't think you provided enough details either way.

Like I'm using Windows own FTP Server to Windows 11/10 to Windows 11/10. Currently, that is using IPv4 IP of the other computer, port 21, no encryption, the Windows username (eg command line: net user) (there's the Windows account user max of 5 char and the full Microsoft account email name that its derived from), and a password....

A Windows local account may be required to get a password to use Windows FTP Sever as you can't for instance get one that works for FTP Sever with modern Microsoft account sign-in using the app password generator from the modern account... so a Windows user with local account is required to have a password that works. As far as I've ever seen and I've tried and been through it.

This all changes with random variations or other things depending on TLS, IPv6, Windows installation differences, the FTP server you use, SSH (SFTP) if you don't use FTP or some other type, and more.

This doesn't even get into setting up the server.

Sorry if it seems like a simple question, but I'm seriously brain dead when it comes to networking.

I'm just trying to set up WinSCP to transfer files between my main PC and another PC connected to my TV that's used as a media player.

My desktop is Windows 10, and the mini PC connected to the TV is Windows 11.

Previously, I had a Raspberry Pi that had LibreElec on it, and I would use WinSCP to transfer files from my desktop to the Pi, but I'm a little confused about the log in since I'm trying to transfer to a Windows PC now.

The Host Name would be the IP address right? I can find that in Windows IPv4 address, is that correct? Also, it seems like port 22 is the default, but how could I verify that?

For the username, I assume that's just the windows username, easy enough.
But what's the password? Is that the pin used for the unlock screen? Or like that password to the Microsoft account?

Also, do I need to enable anything on the mini PC to be able to accept files to be transferred over? I recall needing to do that on the pi when I was running LibreElec.

Again, it's probably a simple question for others, and I love using winSCP, but I always seem to have trouble setting it up when something changes. Thank you all!