You can do that a lot easier by using layouts: https://docs.expressionengine.com/v2/templates/layouts.html
basically, you'll have a wrapper template that contains your basic template, and you feed the content from another template to this template.
This way you only have to use the channel:entries tag once to set all the data.
this is the basic template where i set the variables:
{layout="_partials/_wrapper"}
{exp:channel:entries
channel="pages"
disable="categories|pagination|member_data|relationships"}
{layout:set name="extra_header_content"}<script src="/assets/js/my_extra_script.js">{/layout:set}
{layout:set name="browser_title"}{browser_title}{/layout:set}
{layout:set name="seo_description"}{seo_description}{/layout:set}
{layout:set name="page_title"}{page_title}{/layout:set}
{layout:set name="body_content"}{body_text}{/layout:set}
{/exp:channel:entries}
see me embedding the layout template on the first lin.
My wrapper template looks like this:
<!doctype html>
<html class="no-js" lang="nl" dir="ltr">
<head>
<meta charset="utf-8">
<meta http-equiv="x-ua-compatible" content="ie=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>{layout:browser_title}</title>
<meta name='description' content='{layout:seo_description}' />
<meta name="twitter:description" content="{layout:seo_description}" />
<meta property="og:description" content="{layout:seo_description}">
{layout:extra_header_content}
</head>
<body>
<h1>{layout:page_title}</h1>
{layout:body_content}
</body>
</html>
since you're on EE 2 you'll need to create fields for every browser title in it's own field group. this might be tedious, however if you name the fields a bit logically, you can use preload_replace https://docs.expressionengine.com/v2/templates/globals/preload_replacement.html to make your templating easier:
say you have a channel called news, call your field "news_browser_title" and for the channel called pages create a field called "pages_browser_title"
In your template you can now use it like this:
{layout="_partials/_wrapper"}
{preload_replace:channel="pages"}
{exp:channel:entries
channel="pages"
disable="categories|pagination|member_data|relationships"}
{layout:set name="extra_header_content"}<script src="/assets/js/my_extra_script.js">{/layout:set}
{layout:set name="browser_title"}{{channel}_browser_title}{/layout:set}
{layout:set name="seo_description"}{{channel}_seo_description}{/layout:set}
{layout:set name="page_title"}{{channel}_page_title}{/layout:set}
{layout:set name="body_content"}{{channel}_body_text}{/layout:set}
{/exp:channel:entries}
Update:
You can put your wrapper template in whatever template group you like. I basically have a folder called _partials, which houses all my templates that i embed into other templates.
Say you have a template group setup like this:
_partials
-_wrapper
-_another_template
-_some_other_template
blog
-index
-item
news
-index
-item
in each of your templates in blog or news you can embed the same wrapper template with {layout="_partials/_wrapper"} because it just takes the template_group/template_name as input.
If you need more help, just head over to https://expressionengine.stackexchange.com/ for more specific EE advice
