Ng-Select is an open source project, it is not a part of Angular.io, but could be mistaken to be a part of Angular.
For native Angular select support, use material's mat-select component instead.
The ng-select component can do everything under the sun. Sometimes it shines, other times it's cloudy.
The shiny parts are that for simple list it's great, fast and easy to use.
Complex object bindings needing labels and options templates are difficult.
For example, you want a person's first-name and last-name to appear in the drop-down box. This simple thing requires templates. Once templates are used, the default filters don't work. Instead you must create your own filters. Not well documented at all.
Next time I need a Select Angular control, I'll skip the ng-select and head over to the mat-select instead.