I'm new to Barchetta's, had it a week and now in France. The backlight of the speedometer is unlit for night driving, it this just a bulb renewal and easy to fix?

Most likely yes. Lower the steering wheel to the lowest position, remove two screws under the steering wheel to remove to plastic cover. Then remove the 4 hex bolts that hold the instrument cluster in place, and the whole cluster slides out. Then you remove the cables, twist out the bulb sockets and replace the bulbs.