FTP (File Transfer Protocol) is used to transfer files between computers on a network. You can use FTP to upload files (such as webpages and images) to your website.
The easiest way to do this is through an FTP client. See article: Where can I get an FTP client?
Once you have an FTP client, you will need to configure it to access your Easiest Web Hosting account. See article: FTP connection settings.
If you want to use a tool that is already installed and configured, you can try the browser based file manager available from cPanel. See article: Using the file manager.