many people join and under the guise of "help me debunk this" post RW garbage that an easy google search would show it has been debunked, debunked again and debunked again. Your low post count is not an indicator that, that was your intention, but it fits a well known pattern.
That is why When debunking something always start with the first lie, usually in the first few sentences. Then tell the sender, when it starts as a lie, everything from there on is a lie. Why would you send me stuff you know are outright lies? If you keep doing so I am going to have take the position that you are a liar, for perpetuating known lies.
If that doesn't work, I debunk the next email and send it to all the people he copied it to. usually with a comment on how some people love to be lied to.
If that doesn't work block him and let him know why.