I'm trying to deploying my flutter app to Google play store as a test. On this document, https://flutter.dev/docs/deployment/android, I think I need to store my keystone file private, but I'm not sure how to do it.
I'm completely a beginner to coding, so if someone can tell me how to make the file private, I want to know. I searched to make the keystone private, but could not find and I'm stuck now.