Building Unity APK for Google play- can't find keystore path?

I am trying desperately to export my signed APK after building my Unity project for Android as a "Google development build" and opening it in Android Studio.

I have looked at several other questions and am trying to follow https://developer.android.com/studio/publish/app-signing.html but am having a problem creating my keystore. I have followed the tutorial verbatim but can't create a valid path for the keystone -

I don't understand what I need to do. I have tried /home/users/keystores/android.jks I have tried /home/users/keystores/myprojectname.jks and just sticking it on my desktop. These are the errors Im getting-

I have tried locating android.jks but can't find anything using finder. Is it because I am on a mac? What am I doing wrong here? How can I generate my keystore so I can publish?