Register package names, Android developer checker NO FUNCIONAN LAS APLICACIONES

My apps that aren’t on the Play Store and use Firebase aren’t working.
They’re telling me I need to register them with my signature.

I don’t know how to do it; each app needs a SHA-256 signature and other things.
The PDF is in the Play Console.

Hi dear,

I’m not entirely sure what error you’re referring to, but I believe you need to add the app to your Firebase project.

You can find the SHA-1 in the project preferences.

If you need the SHA-256, you can obtain it by following this guide