The page you see is the page that’s actually set up on your website. Looking at your account, I also see a WordPress installation in there, but the original index.php file from WordPress has been replaced with the page you see now.
To go back to using your WordPress site, please replace your current index.php with the index.php from a fresh copy of WordPress. Alternatively, you may want to replace all WordPress files in case any other files have been overwritten.