Ionic - install problem

I am a complete beginner in Ionic …
I’m on a Windows 10 PC.
I tried to install ionic and cordova:
npm install -g ionic / cli cordova
but there is an error:
npm ERR! code 1
npm ERR! command failed
npm ERR! command git ls-remote ssh: //
npm ERR! ‘git’ is not recognized as an internal or external command,
npm ERR! operable program or batch file.


do you have git installed?