Install NodeJS on Windows
- Browse to NodeJS mainpage: https://nodejs.org

- Run setup binary and just "next" to go

Install NodeJS on MAC
- Download MAC version binary

Click on the .pkg installer to start the NodeJS installation wizard.

Click on Continue and follow the steps. After successful installation, it will display summary of installation about the location where it installed NodeJS and NPM.
Install NodeJS on Linux
For linux-based system, follow the latest instruction for Linux versions on https://nodejs.org/en/download/package-manager/