'npm' is not recognized as internal ou external command, operable program ou fichier batch

‘npm’ is not recognized as internal or external command, operable program or fichier batch

Just add:

;C:\Program Files\nodejs\

To the end of your Path variable on the “User variable” section of the Variables d’environnement on the Propriétés système.

After that, reopen your invite de commandes and type

npm

This should work.