how to get ionic cli?

ionic has Ionic CLI update available: 6.2.2 → 6.3.0
Run npm i -g @ionic/cli to update

according to https://stackoverflow.com/questions/44152737/how-can-i-downgrade-my-ionic-cli-to-the-previous-version-i-had the command does not work anymore due to the name change.

1. uninstall by typing into command line , take note that old way is not working, need to add @ionic/cli
   
1. sudo npm uninstall -g @ionic/cli
2. to install a older ionic, the rest is the same
   
1. sudo npm install -g ionic@4.12.0
3. now to test if the EJSS web app generation works!