The package could not be installed. The theme is missing the style.css styleshee

Hi,

I just purchase a domain name and web hosting, I am in WP dashboard and i downloaded gp premium on my computer hard drive and when I tried to upload gp premium as my theme to work on, I got a message that say " The package could not be installed. The theme is missing the style.css stylesheet. I thought gp premium alreaqdy has style.css embedded, if not, how can i resolve it.

thanks

Sam