The Bowers & Wilkins Formation product line doesn’t contain a device that is acting as a Roon core.
To make use of Roon in conjunction with your Bowers & Wilkins Formation loudspeakers you first have to setup a Roon core in your network. You need a subscription to use Roon. Roon offers a 14-days free trail but maybe you also got a trail code coupon with your product(s).
For further information see:
Roon’s architecture
Why Core?
FAQ: What are the minimum requirements?