No response on npm commands

On installing node js 5.12.0. I’m able to get the node version using node -v but npm commands are not working. Getting no response for npm commands. It’s not showing like npm is not recognized as internal or external… also.

C:\Users\user>node -v
v5.12.0

C:\Users\user>npm -v

C:\Users\user>npm install npm

C:\Users\user>