You can change your meta title, meta description, meta author, and all other meta tags dynamically using JavaScript code. The following example changes the ‘meta description’ tag:
let metas = document.getElementsByTagName("meta");
metas.description.content = "New meta description";
This is useful if you are loading web pages or similar content from a database.
To change the author meta tag using JavaScript:
let metas = document.getElementsByTagName("meta");
metas.author.content = "The author's name";
To change the meta title tag using JavaScript:
let metas = document.getElementsByTagName("meta");
metas.title.content = "New meta title";
Further Reading
How To Set Page Title In JavaScript