Hello,
You cannot simply copy and paste a file to a remote site. First, you need to have rights to add files to the web site. Second, the web site must give you some form of access to the site. Some sites will have a web interface to let authorized users post new files.
Most sites, however, use FTP to transfer files from a computer to a host computer. You can find a number of good free FTP programs here:
http://www.snapfiles.com/Freeware/network/fwftp.html
(I like Filezilla).
You will need to enter the IP address which you should be able to get from the owner of the web site if you are authorized to make uploads. You may also need a name and password that they will supply to you.
I hope this helps!
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