I have been geting these for ages - they said I had a web cam and would tell everyone what I had been looking at - but I don't have a web cam. As others have said, they send out thousands in the hope that a few people will fall for it. Very disturbing when it first happens, I know. I wouldn't even bother to tell anyone, they are not interested in actually doing anything like that, why spend the time - they are too busy dealing with people who take them up.
My garden has been ruined by ????

to all my contacts. Like you they had a password of mine. I sent it to my ISP phishing site (not opening any link) got the standard return email saying they’d received it but probably wouldn’t reply- they haven’t! Deleted it and cleared deleted box and changed my passwords. Not heard anything since even though I had to pay within 48 hours or else! Try not to worry it terrified me but all ok so far.