Since your webserver is a remote computer, access to it is not possible, unless there are special ways to access this remote computer. This could either be via FTP, SSH (e.g. SFTP or SCP), SMB (aka "Windows Network") or even HTTP (where a special "file receive" has to be implemented), to name a few; all different protocols that enable two computers to communicate over the network. Without a special protocol to enable remote communication, file copying is not possible (if I understood you correctly).

So it's not that easily answered in a few sentences and some knowledge about communicating over the network on your part is essential.