How use SYSTEM_ALERT_WINDOW with ionic v6 Cordova

I have implemented the permission for use SYSTEM_ALERT_WINDOW (pop-up window) with permission accepted but I don’t know how use or how show the pop-up window for Android.

I want show pop-up or open the application when is in mode background .

I try with notification push with the property force-start: 1 but not results success, also I try with background mode but I don’t know how show popup

Any help Thanks