Answers for "link to main.js file"

killing a port mac

sudo lsof -i :3000

killing a port mac

kill -9 <PID>

import js in html

<script type="text/javascript" src="yourfile.js"></script>

linking a script .js

<script type="text/javascript" src="path-to-javascript-file.js"></script>

how to link js to html

<script src="Your-JavaScript-File.js"></script> <!--If JS file is in same folder with HTML file-->