https://www.encodedna.com/angular/how-to-show-hide-or-toggle-elements-in-angular-4.htm
<button (click)="toggle()" id="bt">
{{buttonName}}
</button>
<ng-container *ngIf="show">
<div style="margin: 0 auto;text-align: left;">
<div>
<label>Name:</label>
<div><input id="tbname" name="yourname" /></div>
</div>
<div>
<label>Email Address:</label>
<div><input name="email" id="email" /></div></div>
<div>
<label>Additional Information (optional):</label>
<div><textarea rows="5" cols="46"></textarea></div>
</div>
</div>
</ng-container>