Here is how to create a simple Angular 9 application with the Angular CLI in Windows 10.
Step 1 - install Angular CLI
In a command prompt navigate to the folder where you want to create your new app. Then type :
npm install -g @angular/cli
Check that your version of Angular CLI is up to date by comparing the version on the Angular.io website and typing :
ng --version
If it isn't showing the latest version you should:
npm uninstall @angular/cli
npm install -g @angular/cli@latest
Step 2 - create the App
In your command prompt type:
- ng new example (example is the name I am using for the app)
- y when the command prompt asks "would you like to add Angular routing?"
- navigate to the format you prefer using the up and down arrows and hit enter when the command prompt asks "Which stylesheet format would you like to use?" I always use SCSS
After the installation process has finished type :
cd example
Step 3 - run your app
In your command prompt type :
ng serve
Open a new browser windows and navigate to http://localhost:4200 and you should see the following standard Angular welcome page :

You now have a working Angular 9 app.