If you are a complete beginner and about to start learning react, this roadmap is for you.

Javascript

Before starting with React, you should have some prior knowledge in the following JS Topics. Then your way to ReactJS will be smooth.

JS Topics

• Hoisting
• Scoping
• Closure
• Event Loop
• Callback
• Promise
• Async Await
• OOJS (Object-Oriented Javascript)
• ES6 features (specially features related to array and object)

Resources

• JavaScript Basics for Beginners by Mosh Hamedani
• Object-Oriented Programing in JS by Mosh Hamedani
• Introduction to ES6+ (by Dylan C. Israel)
• Modern JavaScript Tutorial (by The Net Ninja)
• Object Oriented JavaScript Tutoria (by The Net Ninja)
• Namaste Javascript (by Akshay Saini)

React

For beginners, I believe, React Doc itself is a good resource to start with. Hence, I gave a list of topics here according to React Official Doc.

React Topics

• Hello World
• Introducing JSX
• Rendering Elements
• Components and Props
• State and Lifecycle
• Handling Events
• Conditional Rendering
• Lists and Keys
• Forms
• Lifting State Up
• Composition vs Inheritance
• Thinking In React
• Context
• Refs
• React hooks
  • Rules of hooks
  • useState
  • useEffect
  • useRef
  • useContext
  • useMemo
  • useCallback
  • Custom Hook
• HOC (Higher Order Component)
• Using Profiler
• Controlled and Uncontrolled component
• Code splitting
• Error Boundary
• Optimizing performance
• React Lazy import

Resources

• React Doc
• Epic React (by Kent C. Dodds)
• Learn React For Free (by Bob Ziroll)
• React Fundamentals (James K Nelson)
• React Tutorial (by The Net Ninja)
• React Context & Hooks Tutorial (by The Net Ninja)