[code] plugin insert code in head

Hello, i have problem with puting meta tags in head.
i’m looking for plugin where i can in my CUSTOM page use some shortocde like:
[code]<meta .... />[/code] and that code embed in head.

I googled a lot and i have nathing. I tried with add_action(‘init’,’myfunction’); but don’t work for me (i put in funciton.php)

i need this for two things setcookie() and for SEO meta tags.

Any help with this?
i also tried with searched about some wp functions but i didn’t have luck.