So I already know HTML, am learning CSS, and plan to learn JavaScript; but what should I learn after these 3?

Question

I simply don't know what to learn next.

Answer 1

HTML
CSS
JS
PHP
SQL

Answer 2

https://www.sololearn.com/discuss/1062064/?ref=app
https://www.sololearn.com/discuss/1033194/?ref=app

Answer 3

Muhammad speaks wisely in his reply. After you finish that list though, you should move onto using a framework like Drupal or Wordpress.org (not Wordpress.com). Frameworks are the way forward in web development.