Do you know what is wrong with my 2006 BMW 330i if ihe service engine soon light is on and then i took it to the auto center and it says that the temperature is below regulating levels and the guy says that it just meant that the car was running too cold

If the code is accurately reporting the problem, it suggests that your thermostat is stuck open. On your car there are two thermostats. One is under the expansion tank, and I don't know what that one does (I have seen it only in the parts book) and the other is in the usual place, top front of the engine. It comes as a single piece with its cover. A little pricey, but if your car is really running too cold, it is hard on the engine and degrades your gas mileage.
Unfortunately, you cannot rely on the temperature gauge in the dash to tell you if it is really running too cold because the temperature gauge in these cars is non-linear. The needle sets right in the middle of the gauge over a fairly wide range of temperatures.