by Anand Kumar on WordPress.org
Header and Footer Scripts plugin allows you to add scripts to WordPress site's and just before closing tag.

Access this page from Dashboard --> Settings --> Header and Footer Scripts
An essential WordPress plugin to easily insert scripts and styles (like Google Analytics, CSS, etc.) into your website’s header and footer.
Looking for a way to add Google Analytics, Facebook Pixel, or custom tracking code to your website’s header or footer?
Header and Footer Scripts is a simple yet powerful plugin that lets you inject code—such as Google Analytics, custom CSS, Facebook Pixel, and chat widgets—directly into your site’s header () or footer.
No bloat, no ads. This lightweight plugin simply does what it says: inserts code into your header and footer efficiently.
All you have to do is add the appropriate HTML code.
Don’t forget to wrap your code with proper tags.
Or for CSS:
The plugin should be compatible with WooCommerce.
Almost all WordPress themes support this “Header and Footer Scripts” plugin. If the codes are not appearing in your site [ask for support] or look at your theme file if they have standard wp_head and wp_footer hooks.
For further information you are welcomed to follow these links: