As your previous degree is on network security and you also worked with the medical records, would you be interested in health information security research area? It is a broad area also. organisational perspectives in health information security, network security etc. or security of health information with the use of IOT devices, teleconsultation, mobile applications etc.
It is just a suggestion but there could be a different area that he might be interested such as data mining or user interface design etc. and if they are related to health area then it should be fine.
You are looking at ‘ this what my supervisor said to me to do a proposal for my PhD. So i need my topic to be in iot security in the perspective of secure the patient information to create an encryption method to secure the information of patient and apply the privacy for them. Or any idea that relevant to the topic. I need a proposal not an essay please.