yarn install specific version

C++
yarn add -D package
//or
yarn add --dev package// for specific versions

yarn add [email protected] are two ways where you can initiate a REACT app.. 
1. Using npm : npm init react-app <app_name>
	 example : npm init react-app sampleApp
2. Using yarn : yarn create react-app <app_name>
	 example : yarn create react-app sampleApp

yarn set version <version>yarn add <package...> [--exact/-E]
Source

Also in C++: