Calendar hacked

I got a notification from the calendar app and opened it and it was an event I know I didn’t schedule because I don’t use the app for that. They’re multiple events scheduled throughout the day for 2 days talking about “protecting your identity” and “ensuring your online protection” (ironic lol) and they’re orange which I’ve never seen before and I have no other option but to “show all notes”. I read other discussions with the same issue but the reason why I’m still thinking it’s a virus is because I watch movies on my phone that has a lot of ads popping up in new pages. Basically I’m asking is if it’s a virus and is it possible to fix the issue on my phone or will I need a computer because I don’t have one right now to delete it on icloud.