angular viewChild for dynamic elements inside ngFor
TL;DR Use ViewChildren instead of ViewChild
As @Commerical Suicide mentioned you cannot set the references dynamically.
The #div is called template reference variable.
You can access your divs via ViewChildren in you *.ts file.
Sample: @ViewChildren('div') divs: QueryList<ElementRef>
Then you can call multiple methods on your new QueryList, like forEach or find.