I'm not familiar wioth the differences between an Atmel 328P and the LGT8F328P. But the Atmel 328P does not support HID functionality.
Does your board has a dedicated chip for the TTL-to-USB functionality? If so, the LGT8F328P does not support HID.
Please post a link to the product that you bought.
Your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with (nor for advice on) your project 
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