yarn add npm code example
Example 1: create react app with npm not yarn
npx create-react-app my-app --use-npm
Example 2: add dev dependency yarn
yarn add -D package
//or
yarn add --dev package
Example 3: create-react-app npm yarn
to override yarn
npx create-react-app my-app --use-npm
Example 4: yarn save dev
yarn add <package...> [--dev/-D]
Example 5: yarn add --save-exact
yarn add <package...> [--exact/-E]