How to add meta tag to specific category posts?

[jambam]

Hi my site is in google news however I want to make sure I stay there and so i want to exclude certain posts in certain categories from appearing in google news by using the meta tags
<meta name="Googlebot-News" content="noindex, nofollow">
How can I add this code to certain posts in specific categorys suh as "how to" and "rants" which arent news.

oddly there is not much info on this on the internet.

Would be helpful if someone could help me out. Thank you!

[not2easy]

The simplest way would be to use robots.txt, but because it is WordPress there is more than one way to find the content.
This is not a paste-in cure because I am not familiar with the specific Googlebot-News UA - you should edit this to fit your needs:
User-agent: Googlebot-News
Disallow: /*rants
Disallow: /*how to
That conveys that any content with /rants/ or /how to/ in the URL is off limits for that bot whether it is /archives/rants/ or /category/rants/

The Yoast SEO plugin lets you add custom metatags on a per post basis. (that part is still free)

[Januar]

You can use Yoast SEO plugin. I think it's a good plugin for adding meta tag for all o your blog's pages.

[londrum]

if you don't mind fiddling with your template files then you can check which category the post is in, and then add the meta tag with something like this:

if(in_category(array('blah1','blah2'))) {
echo'<meta name="Googlebot-News" content="noindex, nofollow">';
}

blah1 and blah2 are the slug names of your categories