In the Control Panel, I have the option to generate and download a Full Backup, but I have not the option to restore it.
How can I do it?

Dear geomino, there must be an option of the backup restore in your Cpane.
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Please open http://help.hostony.com/. There must be a description of Cpanel and WHM.

In case you won't find the backup restore there, try to open a trouble ticket on the Finedesk http://support.hostony.com/ and we'll solve your problem.