What constitutes as scams?

So I blocked a person who I interviewed long time ago from OCAD university, called Simu, on WhatsApp. Somehow he found me and my phone number. This insane creep started to say sorry again about his behavior. I was shocked how he could find my phone number and didn’t get the message of blocking. This was so out of line I felt like vomiting, crying and screaming. I talked to him a little bit and then it was all the same. He started to complain about his life. I blocked him again thanks to iPhone’s blocking. Then right away I saw a news on the New York time about execution of an inmate which was clearly a piece of fake news. I realized right away this must be a scam. It’s a large network scamming. Because on the same day there were another two people find my phone and said I knew them through last year in Toronto which I had no recollection. I reported them as scams and spam. And it’s still scaring me even just writing it down. This is completely criminal, am I right? I’m only not reporting them to police because I think it’s a large network scam that’s not on their reporting range. And it totally is. Anybody can do scams these days. Let me repeat my mantra, stay away from me! Etc.