When my 2000 Toyota Camry sits, mostly over night,or for many hours, when starting white smoke comes out of the tail pipe. I live in Florida so it is not from the cold.
Make sure you are not loosing any radiator coolant, but what you are seeing is most likely just water condensation and nothing to worry about.
White smoke is water, blue is oil and black is fuel. Under some conditions blue might be confused with white.
I don’t think you need to worry. Most cars will give off a puff of white smoke when first started for the day, and this is just the overnight condensation buildup being vaporized. Perfectly normal.