Need Help! Push Notification Firebase Setup

I need help setting up push notifications in Firebase. I know many of you have done the Firebase push notification with great success. I have followed some tutorials on here and they did not work I tried it in preview and nothing. I need step by step instructions please seems some are leaving out steps. This is my first time of doing this so please step by step I want it to be for Apple and Android. Is there a video for this and will it work in preview which I have on my phone? Last I have setup the firebase stuff just getting it to connect. screenshots and step by step or a video please and when you say go here where is here at. Thank You

You have to have a published app before you can test push notifications because the device token created from the preview app will not work.

I tried everything on here not sure if I got it right. I did like much of what you have said. Can tell me how to connect Firebase with AppGyver I wanted it to be for IOS and Android. So, just hooking up firebase to AppGyver please.

Thank You

Hello Just checking back. could you please show me in AppGyver how to connect to Firebase step by Step please.