Behind this error, there can be multiple reasons. It does not depend on a single file or function. It has server involvement.
WordPress wp_head() uses the head section to add meta tags, CSS files, and scripts based on provided priority. It calls all the functions registered with the wp_head hook.
In the WordPress CMS, the theme takes care of the website’s flow, color scheme, design, and many other things containing PHP files, style sheets, images, JavaScript libraries, etc.
Let’s download the fresh WordPress from its official website. to get the latest version of WordPress go to wordpress.org/download and click on the blue-colored button