This internship report examines the practical implementation of Environmental, Social, and Governance (ESG) principles within the banking sector through a case study of United Commercial Bank PLC (UCB), Rangamati Branch, Bangladesh. Conducted during a three-month internship period, the study evaluates how branch-level banking operations align with sustainability frameworks such as Global Reporting Initiative (GRI) Standards, sustainable finance policies, and environmental responsibility initiatives. Using a combination of observations, interviews, institutional documents, and operational analysis, this report explores the integration of sustainable banking practices, digital transformation, financial inclusion, governance mechanisms, and resource efficiency within a geographically unique region. The study highlights practical challenges in implementing ESG initiatives while identifying opportunities for improving sustainability reporting, operational efficiency, and financial inclusion. This report contributes to the understanding of ESG implementation in developing economies and provides practical recommendations for financial institutions seeking to bridge the gap between corporate sustainability commitments and localized operational execution.