Импорт JS в HTML
<script type="text/javascript" src="yourfile.js"></script>
SteDeus
<script type="text/javascript" src="yourfile.js"></script><script type="text/javascript" src="/path/to/script.js"></script><html>
<head>
</head>
<body>
<script type="text/javascript" src=es4.js></script>
</body>
</html>
<script type="text/javascript" src="path-to-javascript-file.js"></script><script async src="https://www.googletagmanager.com/gtag/js?id=G-VB19CSV8XL"></script>