Yes it looks like the wall is painted the turbo nozzle will do a decent job removing some of the failing paint but it will be a lot of work trying to get that all off and some will be left behind unless you really tear up the brick. Overall some being left behind is not necessarily a bad thing the cleaning will give them a better surface to paint on so it will hold up better without peeling. Defiantly a good coat of kilz or something to cover though after cleaning before the final coat.