What Every JavaScript Developer should know

There's so many things to learn to be a FE developer, especially when it comes JS. The real $$$ is JS in FE world. More and more i do study, i'm losing faith in myself and wonder how am i gonna be a proper javascript developer. everyone said i should focus on more on building projects and study myself. Before studying these, i need to know what do i need to know ;( so this isn't easy at all

https://roadmap.sh/frontend
Modern JavaScript Learning Path in 2020
33 Concepts JavaScript Developer Should Know by Nomad Coder 

What to learn before a JavaScript Framework by my hero Brad Traversy

Things to learn before choosing a framework 

JavaScript fundamentals

 - Syntax and basic constructor  

 - Events 

 - DOM manipulation 

 - Functions, loops, conditions 

Modules 

 - ES6 Modules

 - Parcel, Webpack & Babel 

 - Import & Export Default 

Classes 

 - Structuring a class 

 - Constructors 

 - Methods & properties 

 - instantiation 

 - Extending classes 

Arrow functions 

 - scope and "lexical this"

Promises / Asynchronous requests 

 - Learn how to create and receive promises 

 - Standard .then() and .catch() syntax 

 - Async/Await 

 - Learn the Fetch API for making HTTP requests / Ajax (XHR)

Destructuring 

Concept of components & state 

 - Each components have its own data & state of being 

 - Nested components

Spread operator (...)

High order array functions 

 - forEach() - basic iteration/looping 

 - map() - Manipulating the data to create a new array 

 - filter() - Used to filter out certain pieces 

Understanding of concept 

 - clousure 

 - Prototype