I recently received a strange message leading me to a source of where I’m getting a bunch of spam email and I was able to unsubscribe from it.
Go here while being logged into your Google account and check for anything that shouldn’t be there:
Here’s what my account looked like:
Select them all and then click the icon at the top right, which looks like an arrow pointing to the left and a box:
It may take 5 minutes but you should be unsubscribed from all these groups:
Make sure you don’t delete yourself from groups you need to be in – like work email groups.