You can install whatsapp on a virtual android machine on your desktop/laptop. I did that for a while and used a dumb phone (new nokia 8110) as my main phone and

You can install whatsapp on a virtual android machine on your desktop/laptop. I did that for a while and used a dumb phone (new nokia 8110) as my main phone and hotspot for a while. I kind of enjoyed it, but a couple of things made me give up for now.: First, abysmally bad battery life when using it as a hotspot (and no auto wifi disable when no devices connected). Second, laughably slow charging. Like, not even net charging when using lots of data via wifi hotspot and even in best case something like 4 hours to charge from empty to full. I am still keen to buy a dumb phone that fixes these.