How to inject HTML code in the head only on home and post pages

Hi, I wanted to know if there is a way to inject an HTML code to the <head> section, only in the home page and post pages?

Thank you.

I believe that what you want to do is add code to the script that checks the URL and fires only when it’s on the pages you’re interested in.

The code is Adsense auto ads in the header. Should I then create a conditional statement in javasciprt and rewrite that code to insert the javascript then?

Yes, you may try to read the Developer’s guide to Discourse Themes. For Adsense I recommand you to try Offical Adversting Plugin if you didn’t.