first you are using Galaxy Watchface STuido not Watch Face Studio so I moved this.
GWS is for Tizen based watches Galaxy Watch3 and older if you are trying to build for Watch4 you need Watch Face studio
The first time connecting can be confusing especially with the documentation being generic and not for specific watches.
You are running SDBoverBT and that only works with Galaxy Watch and older devices it won’t connect to Active2 or Galaxy Watch3.
Your image should show the selected device, Since it isn’t showing you either didn’t select the device on your phone or you do not have a compatible device.
What you are getting is the way to generate the Developer’s Certificate ID.
I’ll check back this weekend and Monday if you need help but read the information on Distributor Certificate and connections in the FAQ it may help.
Samsung Developer Relations
Clear up what you are doing and I can help you or point you to the correct information. Start with the GWS FAQ for connections and certificates.