Has my iPhone been hacked?

I watched a TikTok and then decided to research about the topic and didn’t expect anything to happen until a warning showed up saying “Your iPhone has been hacked!” I can’t explain much but it had many sentences and warning logos. I exited as fast as possible of that site due to it scaring me a little and just cleared it from my history. It also then led me to the App Store. I read the comments about the app and most of them mention the hack. Supposedly it’s a scam app but is this true? I want nothing to do with it.

Have I been hacked and what can I do to remove it? How can I prevent from clicking onto unknown sketchy sites again?