Header.php help

I just made a post titled header.php and when I tried to edit it, I got a message saying that this topic is closed to new replies. What’s going on with that? Did I do something wrong?

I tried to validate my site with google, and found out I didn’t have a robots.txt file, so I inserted one in the root dir. The site has not loaded since. I can access all the files in the root, but can’t access WP.

Is there any way I can get someone to check my header.php file for errors on: https://sidneysuccess.com

Thanks very much!