How to record PC audio output in S1 w Audio box USB

I want to record the audio output from my laptop on Studio One. I think I'm set up OK - my monitor speakers are playing back fine through the Audiobox interface, but I caot see what to do for Studio One to pick up the signal as an input to record. I can only see Inputs 1 & 2 - the XLR inputs as options - what do I need to do to get S1 to 'see' the computer output so I can record it?

Ruing Windows 10 on Samsung series 7 ultra laptop

Thanks!