Enable TypeScript support in a Next.js app

Next.js comes with TypeScript support, but it is not enabled by default.
📜 What is Typescript? Check out the Typescript Docs 🧩 Briefly Typescript is a language that is a superset of Javascript. Perhaps the biggest feature it provides is static type checking.
Create an empty tsconfig.json in your project's directory
If we try to run yarn dev now then we'll get an error because we need to install the necessary typescript packages (typescript, @types/react, and @types/node) which we can do by running this command: yarn add --dev typescript @types/react @types/node
This will populate the tsconfig.json file with values.
By default strict mode is turned off by default; however, in order to write better code, go to tsconfig.json and change "strict": true and add "strictNullChecks": true right below it.
This will help us avoid the vast majority of run-time issues
The last name is to rename index.js to index.tsx
We can test to see if everything's working by adding a typed variable to our index.tsx:
JS
```
const title: string = "Next.js + Typescript";
```