You know not to trust that site with any more information. Once the alias is deleted, anything sent to it will result in a delivery failure and you won’t get any more spam from anyone they sold that address to.

If your mail server supports aliases, you can make one for each site you sign up for. Then if you start getting a bunch of spam, you can delete the alias and you will know which site sold your information.

Some TLDs that are well known for spam get blocked. If you stick with a .com, you will usually be fine if you are using a decent mail server.

Tapes are how you back up large amounts of data. A small tape robot can handle petabytes.

So can you run sudo rm -rf C: to remove the malware now?