If you’re talking about editing detected devices, you can navigate to your Devices screen and click any device to edit details about it.
If you’re talking about manually teaching Sense what’s on in your home (which it seems like you’re insinuating), then you’re right. That is not possible and we have never said it was. It has been discussed at length on this forum why it’s not possible, but this is the most concise read on it: Why can't you train Sense?