I want to stop receiving any messages in iMessage

I do not use an iPhone, and I never have. Recently I started receiving texts from some iPhone users on my Mac or iPad *only*. They come in to iMessage. I only use these devices very rarely, so I end up accidentally ghosting these people for days because I don't get the messages on my phone.

How can I permanently stop getting messages in iMessage on these two devices? I simply want to receive all text on my Android phone as I always have. I'm not sure how this started.