How to sign my app?

I wanted to upload my game on the Google Play Console, but it says:

Does anyone know how to sign the app? I habe absolutely no clue…
Thanks in advance!

I had the same problem and I solved it like this:

I hope to be useful :wink:

Thank you :slight_smile: I found a tutorial online. It´s german, but Google Translator did a good job and it worked: Link