Install different versions of JDK and JRE in local and switch between them easily.

Go to below jdk 14 downloads page at the URL https://www.oracle.com/java/technologies/javase/jdk14-archive-downloads.html. You can also reach this page by searching in google for the same. 

Click on the download symbol corresponding to your installer. Here it is macOS Installer.

We have a content type named 'Q & A'. Go to Structure > Add Content > Q& A and nvaigate to Question text area section. Or click here.

Select the text format as FULL HTML.

Start typing the code in text area

Once you have started writing the code, click on Source option in editor toolbar,

Add below lines to package.json

"bootstrap": "4.0.0-beta.2",

Run npm install on the project folder to download the files.

For the project to identify the javascript and css files add below lines to angular-cli.json

"styles": [
        "styles.css",
        "../node_modules/bootstrap/dist/css/bootstrap.min.css"
      ],

/bootstrap.js to scripts tag

"scripts": ["../node_modules/bootstrap/dist/js/bootstrap.js"],

Angular is a single page application. Single page served by angular is index.html. Below is the structure of default index.html.

<app-root> is a tag present in index.html. How angular will know about this tag. That is taken care by main.ts which is the first script that will run. Below is the structure of main.ts