I want to add this library to my local project, I don't want to install npm.
Can I just add the library to my project manually? if yes how?.
I have small experience with javascript, I just want to do a simple project.
I think all you need to do is download the js file from the lib https://github.com/komagata/textarea-markdown/tree/master/lib directory and include it as a script take in your project: <script src="path/to/js.js"></script>