I did get the yellow can, defeated the ghost girl, and open the blue blocks, not in that order, but I don't know how to disable both of the blocks
if you referring the stage 3, you cant ''beat'' the level at the moment, in the room with harpy graffiti and two blocks (red and green) is a dead-end, it's intended to halt player from progressing
bring the yellow spray can to stage 2 and beat the secret boss in there (afterward you can visit two extra stages from what i heard)