Outdated from Nationwide: Level 2 epidemic warning

A friend told me that people living in the home count collectively as one person. So for instance if 4 people live together then they can invite 4 more people over. I can’t find any resources about this in English. Is it at all true?
It makes sense in a way because otherwise, 6 people living together is immediately against the rules. But I also feel like the CDC wouldn’t go out of their way to make this type of specific exception.