Energy efficiency is a key priority for the European Union in its efforts to decarbonize the building sector. Achieving this goal requires the adoption of electrified low-carbon technologies, including smart energy management systems. Additionally, building digitalization and occupant-centric control strategies are crucial for optimizing energy performance while ensuring indoor environmental quality. This paper presents a structured workflow for implementing advanced operational strategies in HVAC systems within non-residential buildings. The proposed approach is based on a Digital Twin framework, enabling energy use planning and optimized control strategies that integrate indoor environmental quality and occupant-centric metrics. The methodology includes data acquisition from IoT sensors, real-time modelling for predictive control, and intelligent decision-making algorithms to enhance building energy performance. The workflow is currently being implemented in a newly constructed office building in Spain, serving as a case study for real-building adoption. While full deployment and validation are ongoing, preliminary findings suggest that this approach has the potential to improve HVAC efficiency, reduce energy consumption, and enhance occupant comfort simultaneously. Key challenges identified include interoperability with existing building systems, high initial investment costs, and the need for specialized expertise in Digital Twin integration. These insights contribute to the ongoing development of data-driven smart energy management solutions for non-residential buildings.