How do I set up an ergonomic home office?

Polly wants to dump her laptop for a more ergonomic computer due to neck and shoulder pain I’m an academic with neck and shoulder problems and fear turning into a hunchback through too much peering at the screen. I’m now moving house and setting up a home office. I want to dispense with my laptop – the source of my problems – and buy a desktop and an ergonomic keyboard.I’m confused about whether to get an all-in-one or a PC with a separate monitor. I am only really