Off topic, I have a synology NAS, what is a good camera that only communicates within my lan and doesn't reach out to any servers on internet? We need to setup

Off topic, I have a synology NAS, what is a good camera that only communicates within my lan and doesn't reach out to any servers on internet? We need to setup a camera for insurance purpose in my mum's house in France after multiple burglaries but I absolutely do not want to give access to a third party.