Jane:
Silly thing to do. Every so often a genuine mail will end up in automated spam catchers, usually people you may not have heard from for a while.
You do not need to open them to see who they are from. Check, then delete as appropriate.
As for people suggesting using a viruschecker to deal with ransomware: Sorry, this is not the tool for ransomware, virus checkers are for virusware, for ransomware you need ransomware tools.
I have had a few of these demands and even without ransom tools they can be got rid of:
My first action is to open taskmaster (ALT-Cntrl-Delete) and just delete the process second, just go to restore point and choose last known good configuration.
Then run Malwarebytes, Spybot search and destroy and clear cache.
Ensure all drivers and firmware is up to date, avoid Microsoft browsers and emails ( thay are the biggest target to hackers), use a more secure browser such as Firefox, use a VPN and the one good Windows security product......Windows Defender Security Centre.
Sounds like a lot of chores if you just run a PC and hope for the best, but essential nowadays.
Like anything, just get a routine going.