SHELL

install ionic globally

$ npm install -g @ionic/cli

install ionic

npm uninstall -g ionic
npm i -g @ionic/cli

ionic install

npm install -g @ionic/cli

Install ionic

//First, install node.js: https://nodejs.org/

//Run in your terminal
npm install -g @ionic/cli

//If there was a previous installation of the Ionic CLI, it will need to be uninstalled due to a change in package name.
$ npm uninstall -g ionic
$ npm install -g @ionic/cli


//source: https://ionicframework.com/docs/intro/cli

install ionic

To go git bash or command prompt and type the following:
	npm install -g @ionic/cli

To install Cordova and Ionic, use 
	npm install -g ionic cordova

install ionic 6

npm i -g @ionic/cli

install ionic version

npm install -g ionic@VERSION