What Is Router outlet?
The Router-Link, RouterLink-Active and the Router outlet is directive provided by the Angular RouterModule package. It’s provides the navigation and URLs manipulation capabilities. It also renders the components for specific location of your applications.
Both the template and templateUrl render the components where you use this directive.
<router-outlet> </router-outlet>
For
more detail kindly refer the link - https://www.code-sample.com/2018/05/angular-5-6-7-routing-and-navigation.html