To add external JavaScript files with script tags in React Next.js, we add the script tags into the Head component.
For instance, we write
import Head from "next/head";
const Layout = (props) => (
<div>
<Head>
<script type="text/javascript" src="..."></script>
<script type="text/javascript" src="/js/myscript.js"></script>
</Head>
<p id="demo"></p>
</div>
);
export default Layout;
to add the script tags into the Next.js Head component.
