So far, I thought that 'Do you want to go out for lunch?' has exactly same meaning as 'How about going out for lunch?', as both sentences are giving suggestions.
However, I recently read that 'Do you want' sentence asks listener's simple wish or hope, while 'How about' or 'Why don't you' sentence is giving suggestions.
If that explanation is correct, then how can I distinguish each sentence's meaning? Or can I still use both sentences for giving suggestions?