I'm 14 I went on my new dads phone and it said security check I couldn't get out of it and it's an iPhone 6s?

Does this mean it has a virus I Got rid of the pop up and its working now is the mere a virus still in their or is it gone?

Read more: I'm 14 I went on my new dads phone and it said security check I couldn't get out of it and it's an iPhone 6s?