Install Node.js® and npm if they are not already on your machine.
Verify that you are running at least node 6.9.x and npm 3.x.x by running node -v and npm -v in a terminal/console window. Older versions produce errors, but newer versions are fine.
Then install the Angular CLI globally by running:
npm install -g @angular/cli
The Angular Command Line Interface (CLI) is a tool to initialize, develop, scaffold and maintain Angular applications. For more info about the Angular CLI visit https://github.com/angular/angular-cli/wiki
Go to the folder you downloaded the project files, unzip it and open a terminal in that folder.
npm install to install all the project dependencies.