If you have an FTP server installed, then there are many FTP clients that you can use to upload files to your server. A good free FTP client is FileZilla available from http://filezilla-project.org/.
Viewing all files on your server securely
The best thing to use is WinSCP which is available from http://winscp.net/eng/index.php
Documentation is at http://winscp.net/eng/docs/start
This is a very easy piece of software to use, if you use it in Explorer mode then it is like browsing the files on your own computer.
Please note that with WinSCP you have full access to all of the files on your server - including important system files. Don't edit or delete any files if you don't know what you're doing. If you break your server then we can't take responsibility for this, you will probably require a reinstall.
If you are looking for your web files then they will usually be at one of the following locations:
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