NPM is a NodeJS package manager. So, in order to install and use npm you have to install nodejs first. For Windows there's an installer here: Download | Node.js .

To install nodejs on your local machine, follow these steps (this will also install npm):

• install the downloaded nodejs package
• check in your terminal the version:  node -v  ,  npm -v 
• navigate to the project folder where you want to use npm
• to install npm for this project/in this folder, use:  npm install 

Now npm should be up and running within your chosen folder.

To update npm use the command:  npm install npm@latest .