Question: I have two angular application say A and B. Now in B application's One tab i want to **load entire application A**. How do i achieve this?

Please let me know how to achieve this functionality. Does angular has any special tag which i can use

Answer: 
You want something like MICRO front ends, build Application A as Angular custom element (web component - Angular Elements), the output will be a script. Load this script in Application B. place the selector which you provided while creating a custom element in Micro App B where ever you want to load App A.

For More read about Micro Front Ends ([Angular Elements](https://angular.io/guide/elements))

Please don't use iframe they become really difficult to manage, To know more read a little about Micro Front End with Angular there are lots of well-written blogs on the same.
As Akshay mentioned you could use Angular Elements to expose your app A as a custom element and use it in app B.

In your case, you want to expose your AppComponent as a custom element.