Как кодировать JavaScript
console.log("Hello World!");
Good Grasshopper
console.log("Hello World!");<!--just open a file with the ending of ".js"
example: myFirstJS.js
an other option is to write this sentence on HTML document:
-->
<script type="text/javascript">
//write here your code
</script>//checkout freecodecamp
https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/basic-javascript/