How can I check if my phone is hacked?

A pop up came in from Sky claiming I was one of a few chosen for a short survey and prize. I answered some multiple choice Qs that needed to be answered in 3 mins or something - only a handful and all about Sky and then asked to choose prize from iPhone/Samsung phone/Ipad Air. Clicked the phone - then it asked for details - I got as far as first name and then went onto iMac which I was working on and checked out the website that was now in the browser something like seabreezeskyblue20 or something - looked it up and it went t trust site that said it was very untrustworthy and a scam etc. Immediately closed down the page after deleting the info I'd put in and then there was an apple pop up that said I've been hacked...

I did read some other posts and go into settings and clear my browser history and close tabs - but the other Qs and answers didn't say how I could tell if I had actually been hacked.

My iPhone has been updated to the latest IOS