Should i know all wordpress function for becoming a good wordpress developer ?!?! They are more than 3000 functions!! :-(

Question

I know html,css,javascript,php and sql. I want to be a wordpress developer. But i don't know what should i learn and what ability should i have. :-(

Answer 1

✔ Html
✔ CSS
✔Php
✔ JavaScript
popular wordpress dev use this

Answer 2

I mean after these . ;-)