This shade is a classical Candy Red. The suitable undercoat is included in this kit. You are buying 2,0 litres undiluted base paint, the kit contains 1,0 litres of the undercoat and 1,0 litres of the effect paint.
RED CANDY is "ready to paint"... this means it is not a Candy varnish and can be applied like "normal" metallic paint and can thus be repainted or retouched hazzle-free.