So, with the server files, I'm looking to upload them to my server. However, there's only simple server files for 6.0.0, is there no way to obtain just the server pack?
i dont understand what is to do with the v6.0.0 server "files".
what i have to do with the manifest.json, modlist.html and overrides??? do i can delete them, how can i download the full server files?

The simple server files are designed to automatically download and install the pack. You have to run the starserver.bat or startserver.sh for it to do that.