Some providers provide a tool call Hsphere Backups, it cna assist in backup of your sites contents and databases. If you do not have this, you can still do site backups with the Webshell(in ftp users drop down, File Manager link). From there select all folders and use the "Archive" button at the bottom of webshell. This will get site content, you will have to use phpmyadmin or another tool to generate a SQL dump.
As for email, it will be all manual from what I know, especially if you just have a reseller account. Even if you don't, cpanel and hsphere use different mailservers, and a migration would be hard.