wp-install Will Not Load – Please Help

I’m trying to install WP for a client. I’m not the techie type, but the basic installation seems pretty easy. I created a MySQL database, unzipped the directory to my local folder, inserted the DB details into wp-config-sample then saved it as wp-config.php I then placed all of the files inside original folder into my public_html folder and uploaded then.

When I go to the site thesite.com the screen is blank. When I go to thesite.com/wp-admin/install.php a screen pops up like I’m trying to download install.php

This is driving me crazy, can anyone help?

Thanks in advance.