How To Install WordPress Using Softaculous

Please help me on this. I suspect that someone hacked my blog. At first, the hacker changed my ” about me ” page. The next time I opened my blog, it looks like this:

Warning: require(./wp-blog-header.php) [function.require]: failed to open stream: No such file or directory in /home/stretchm/public_html/index.php on line 17

Warning: require(./wp-blog-header.php) [function.require]: failed to open stream: No such file or directory in /home/stretchm/public_html/index.php on line 17

Fatal error: require() [function.require]: Failed opening required ‘./wp-blog-header.php’ (include_path=’.:/usr/lib/php:/usr/local/lib/php’) in /home/stretchm/public_html/index.php on line 17

I sent a message to my web host and instructed me to re-install wordpress using softaculous in my cpanel.

Please provide steps on how to fix my blog.

Thanks.
Jsnis