Yes. The hair can be colored.
As a general rule it is easier to darken the hair than to lighten the hair. We recommend dyeing darker, since it is difficult for the original colour to fade. Improper dying will ruin the hair. We highly recommend your hairdresser dye the hair. Coloring by yourself will take a risk of not coming out the shade you want. Please always use good quality products and test a small sample first, if you can't get to a salon.