Fatal Error wordpress/index.php/ on line 2

I uploaded a new theme from an unzipped file through my FTP, went back to my hosted wordpress page, http://www.igroupadvisors.com/wordpress, and see this error message

Fatal error: Call to undefined function get_header() in /home/content/62/9488662/html/wordpress/index.php on line 2

I am not sure if this is referring to the theme that I uploaded or if there is another problem within my wordpress files.

Thanks in advance for your help!