No, that’s not how it works in the general case. There are ways to setup a house to back power but it’s more complicated than just plugging it in.

So what you’re saying is that the general case is that it feeds back into the grid unless there are additional measures taken? But at the same time, it’s not the general case? Huh?

Without proper safeties in place back flowing power to the grid becomes extremely dangerous for line technicians

Which is why, where I live, you have to register your devices with the utility company.