Am being bombarded with sites or emails coming to my email address. I get about 40 a day.?

They come in on all sorts of crazy names that are different all the time. Though I never subscribed to these sites , I have tried to unsubscribe to them but when I press the tab to submit , a note comes up that there is no such email address or it can't locate this address. I've tried to mark these as phising scam , junk, etc., etc. but as they come in under hundreds of new names all the time, nothing seems to be working to get rid of these emails on my computer. could someone please tell me a solution to get rid of these. It would be much appreciated. Thank you.