Concise API Error Handling

Proper error handling is not something that, is well covered in books or tutorials, most times we have developers having to revisit code because of cases not thought of or they end up having to write repetitive code.
Going through lot’s of projects by different developers, one thing always stands out which is the way we handle errors. These include:
1. An api returning incorrect data
2. A resource being unavailable
3. An api exception or just simply identifying and classifying error codes.
I would like to throw more light especially to intermediate devs on how to structure their code to reduce the amount of time spent redoing error handling and how to classify these error cases to generic master pieces to properly handle and send feedback on errors.
This talk will also handle cases with LiveData and retrofit errors being propagated down to the view.