No worries. What would be required to happen (assuming your phone wasn’t already compromise), is for you to have been transmitting sensitive information to the internet.

Think of it as a thug who’s waiting just down the street. He’s dangerous, but you never left your house so you didn’t get robbed.

So there’s two different attacks to worry about with wifi:

1. data “snooping” - in theory, anyone on the same network could pick up the data you’re sending to someone else. This is what VPN services like to scare people with in their misleading ads. But everything we do on the internet nowadays is encrypted, scrambled so that only you and the intended recipient can read it. To anyone else it’s just jumbled-up garbage.

2. hacking or infecting your device - this would need a serious security flaw with your device, and the attacker taking advantage of it. In 2023, this is very rare, especially on iPhones which have good security. I’m not saying it’s impossible, but it’s very rare and hard to do. I’m not aware of any current attacks like this.