Can't set up Mac Studio with old Magic keyboard

it appears that the old Apple Magic keyboards aren't quite magic enough to be allowed to pair with the new computers during startup.

I can't believe that apple would design a product that deliberately can't be used with its own pripherals, so how do I start up my Mac Studio when it's not recognising my apple bluetooth keyboard.

The answer isn't

Open bluetooth settings.... because we haven't got that far

The answer isn't

Just connect its lightning connector ... because it doesn't have one. It is, however, an apple made bluetooth keyboard that is capable of being discovered.

So how do I get my Mac Studio to recognise it?