This one I know is a straight up lie, because I remember where it came from: Trump asked an expert if it was possible to use disinfectant inside the body, was immediately shut down with a simple "no", and dropped it. Audio of the conversation was leaked and immediately twisted into "drink bleach", ignoring everything else about the conversation.

Also UV light treatment actually exists, just not for this purpose. It's a completely normal thing to ask once you learn UV kills viruses.