Where do I find the tags?

Ok, so I'm still learning where everything is and I'm starting on my path to SEO marketing. I read that I needed to write a descriptive  title for my webpage. Ok, I got that! But where do I find the Header tags to accomplish this step? I thought it might have been in my .htaccess file but I was wrong. And I tried looking at my index file and that didn't seem right either. Can anyone guide me in the right direction? This is one of the simple steps that I will look back on and be like........ Duhh!

Hi, make sure to make a backup of your files before you edit...

templates/base/_header.html

<title>__page_header__</title>
<base href="<bx_url_root />" />
<meta http-equiv="Content-Type" content="text/html; charset=__page_charset__" />
__page_description__
__page_keywords__
<meta name="copyright" content="Copyright - All Rights Reserved Michael Newton&copy; 2004 - 2010"></meta>
<meta name="robots" content="All"></meta>
<meta name="cache-control" content="no-store"></meta>
<meta name="pragma" content="no-store"></meta>
<meta name="author" content="Micheal L Newton"></meta>
<meta name="revisit-after" content="1 Week"></meta>
<meta http-equiv="Content-Style-Type" content="text/css" />
<bx_include_css />
<bx_include_js />

I added the colored code for my sites...

Thank you very much