パスの設定
windows
Just add:
;C:\Program Files\nodejs\
To the end of your Path variable on the "User variable" section of the Environment Variables on the System Properties.
After that, reopen your command prompt and type
npm
This should work.
Mac
If you installed Node.js using Homebrew, npm binaries can be found in /usr/local/share/npm/bin.
You should make sure this directory is in your PATH environment variable. So, in your ~/.zshrc file add
export PATH=/usr/local/share/npm/bin:$PATH
I think the npm path is not created.
Fixing npm path in Windows 8 and 10
https://github.com/HashLips/hashlips_art_engine/issues/1283