Hello Giginana,
iPhone isn't capable of Fall Detection, this is an Apple Watch SE and Series 4 or later feature - Use Fall Detection with Apple Watch - Apple Support.
iPhone 14 models only support Crash Detection - Use Crash Detection on iPhone or Apple Watch to call for help in an accident - Apple Support.
To my knowledge, you cannot disable the feature to call emergency services and only contact emergency contacts. You will be given a prompt however when a crash is detected. If you do not want to call emergency services, just tap on the Cancel button.
You can toggle the feature off altogether, but I wouldn't recommend it. Even if it is possible to disable the feature to call emergency services and only contact emergency contacts, I wouldn't recommend it either. The feature is mainly for contacting emergency services so they can get to you quickly. It comes in handy when you're not able to respond. If you don't respond in a certain amount of time, iPhone (or Apple Watch) will call emergency services automatically where help will be sent.