Hi kenli,
I’m guessing you are referring to this blog post when asking about preventIndexing? I think that was just an example of how to use strapi to manage the seo metadata that appears on your frontend.
From that blog post, they show:
{
preventIndexing && (
<>
<meta name="robots" content="noindex"></meta>
<meta name="googlebot" content="noindex"></meta>
</>
);
}
These metatags should be implemented using your frontend framework. I recommend you look for documentation from the frontend framework on google indexing. For example, if you are using next.js, check out this resource.