In your case,

I want to cache the response so that I can use the app even if it is offline

You need to implement a local database to save data on the user's device. and this is possible using the Room Database. This is how it works:

When Online

• You fetch the data from the server
• show it to the user & update the local database

When Offline

• Show data from the local database

Please check MVVM News App (retrofit) with local db