Welcome to the #Phish_pond.

This type of scam is circulating. See below a screenshot. Typically they are sent to a large number of email addresses retrieved after a certain breach. In this case the scammer obtained the email addresses from a mailing list. The scammer demands a payment in either cash or Bitcoin threatening to expose your secrets. In most cases they have only your email address and nothing else. In some rare cases they may list an old password (retrieved from past data breach such as LinkedIn) of yours in order to convince you.  Do not re-use passwords.  And of course do not answer those scams (even for fun!)