Set notification large icon on android app through fcm from sever when app is inactive

[Tina Tahmasebi]

Hi,

How can I set a large icon passed by the fcm from the server to show on the android app as a notification when the app isn't in the foreground?
When I receive the notification it's like a big image and is not an icon.
It is related to this [link] but there was no answer for it.
Also, how can I group messages when the app is inactive?

[link](https://stackoverflow.com/questions/54266408/push-notifications-set-large-icon-when-sending-from-server)

Thanks