js how to use variable declared in template code example

Example: set variable inside div angular

// Synchronous:

myVar = { hello: '' };

<ng-container *ngIf="myVar; let var;">
  {{var.hello}}
</ng-container>
// Using async pipe:

myVar$ = of({ hello: '' });

<ng-container *ngIf="myVar$ | async; let var;">
  {{var.hello}}
</ng-container>