It looks like you have mistyped both acronyms. I guess that by "STPF", you have meant "SFTP". But I won't even try guess what you have meant by "TPFS".

But I'm being told NOT to use STPF. I'm supposed to use TPFS instead. Are they actually one and the same?

To use FTP over TLS/SSL (aka FTPS), select FTP for "File Protocol" on the Login dialog dialog and then select "TLS/SSL Explicit Encryption" for Encryption.
https://winscp.net/eng/docs/ui_login#session_settings

This morning while FTP-ing to my website on SimplyHosting.Net, I was locked out and refused entry. At the same time, I could no longer get to my website using the Firefox browser. I filed a ticket with SimplyHosting and was told:

Upon checking we could see that your IP address was blocked on the server firewall due to failed SSH login. I have unblocked it now. Please try to connect with FTPS instead of SFTP.

I have used WinSCP for years, same website, without a problem until a few months ago when I was similarly blocked. I have no idea how to use FTPS instead of the SFTP I'm apparently using. I've been through all the options on the menu bar and searched the WinSCP website but am not wiser.

Please, how do I resolve this so it doesn't happen again?

Thanks!