iPhone 11 Pro battery replacement

I took my phone in to get the battery changed out cause it's the only thing I have an issue with and the guy at the store scared me away telling me how changing it could then cause the Face ID or other features to break and then I would be liable to pay for them because my phone is out of its warranty. Is this true? If so how often does that happen?

it was an authorized apple repair place but the way he was so unable or unwilling to answer my questions felt like he would potentially try to scam me /was trying to get a sale because he then shifted to how I should just buy a new phone even though mine works perfectly fine minus the battery needing replacement.