Vueling has been through a lot of branding changes over the years, so there isn't a traditional business class, but there are various fare bundles and seat options which means (e.g.) Priority Boarding and Row 1 seating for a premium price.

Vueling has Space One (row 1), Space (exit row) and Space Plus (row 2, 3 and 4, which thanks to IAG centralisation give a little more space than the seats down the back). If buying via BA, I think that you get Space, but not Space Plus or Space One, but the OP can perhaps confirm with a little more detail what rows they are seeing as available on the VY app.