You can upload files to your site through cPanel's File Manager interface (Home >> Files >> File Manager). Click File Manager, and then scroll down to the directory in which you wish to put the files.

You can also use an external FTP program to upload files. To do this, perform the following steps:

  1. Create an FTP account in cPanel's FTP Accounts interface (Home >> Files >> FTP Accounts).
  2. Enter your  public_html directory in the Directory: text box.
  3. Use your external FTP program to upload your site's files to that directory.