Importing old data to reinstalled OJS


We got a reinstallation of our OJS. We now have a subdomain where we can recreate our original site. How do i import our public_html files and databases from our old site to the new one? I logged in our cpanel but everything there is from our old site.

Our goal is to totally duplicate our old site to this newly reinstalled OJS. Any step by step guide will be a GREAT HELP. I am using Windows by the way. Thank you!!