Fake Apple Security Pop Up Ads

In the last 2 weeks I’ve received several pop up ads claiming to be Apple Security that has found 6 viruses on my device and that ad pops up when ever I played Trivia Crack and I’ve let them know twice and stopped using that app. I’ve also been getting lots of those CONGRATULATIONS!! Pop up ads (It varies what company it claims to be from) and it’s never happened while on Facebook it’s when I’m using Google and doesn’t matter what website I’m on or if I’m doing a Google search. Ive always had Block pop ups ON in settings and I’ve cleared all my data & cookies which stopped it for a few days but now it’s happening again but not several times a day like it was before before. I use Safari with Google browser and it happens in both Private mode or normal mode. It’s freakibg me out a little because I thought Apple had great security and stuff like this wouldn’t happen so I’m not sure what’s going on or what to do?? Thanks in advance