This paper suggests a secure architecture for Remote Patient Monitoring (RPM) systems that integrate Azure IoT Hub, Azure Digital Twin, and OPC UA in order to enhance the security of patient data, data privacy, and personalized healthcare services. RPM systems track real-time health data of patients through wearable devices. In this process, they face significant security challenges specifically related to data encryption, access control, and compliance with the security requirements of regulations like HIPAA and GDPR. To overcome these concerns, the proposed architecture in the paper utilizes OPC UA for secure and compliant communication between healthcare devices and the cloud. An additional level of security is provided by the implementation of pseudonymization. Moreover, the personally identifiable information (PII) of the patient is removed before transferring to the cloud and hence assures compliance. Azure IoT Hub makes encrypted data flow in the cloud which is then transferred to Human Digital Twin (HDT) for real-time analysis and enhancing personalized healthcare. The integration of multiple layers of security, including role-based access control (RBAC) and encryption, in the architecture protects against data breaches and unauthorized access. The suggested architecture provides adequate security features compared to existing RPM systems, as indicated by statistical analysis using the Chi-Square test. This test was performed for security metrics like Data Encryption, Access Controls, Secure Data Transfer, Data Privacy, Regulatory Compliance, Cloud Security, and Audit Logging.