I’m a leftie and I don’t think I learnt it. My mother said as a very young child she noticed I’d mainly used my left hand to take things - probably food :)
These days the only real problem for me is scissors, especially the ones with moulded plastic handles.
I didn't mean that most people don't have an innate handedness, but that it's quite possible to learn to do tasks with your non-favoured hand - it just takes a period of adjustment during which it feels incredibly clumsy to use that hand.
