The National Education Policy 2020 necessitates a paradigmatic shift in higher and technical education in India from linear, content-driven instructional models toward adaptive, competency-based, and multidisciplinary learning ecosystems. This transition foregrounds holistic learner development through the integration of arts, humanities, languages, values, and well-being practices with science, technology, engineering, and mathematics, thereby advancing a STEAM-oriented educational paradigm. However, a critical challenge persists in operationalizing these policy-level directives into coherent, course-level curriculum architectures that effectively respond to the complexity of contemporary skill requirements and rapidly evolving technological landscapes. Addressing this gap, the present study adopts a case-based, design-oriented research approach to develop and validate an NEP 2020-aligned Outcome-Based Curriculum (OBC) framework for undergraduate engineering education. The framework conceptualizes curriculum design as a multi-layered, dynamic system, integrating Program Educational Objectives, Program Outcomes, Programme Specific Outcomes, Course Outcomes, and Session Outcomes into a hierarchically aligned and recursively connected structure. This architecture enables constructive alignment across cognitive, psychomotor, and affective domains, while embedding feedback loops for continuous refinement and outcome attainment. The proposed model incorporates experiential, workflow-based, and technology-enabled learning processes, including micro-projects, complex engineering problems, laboratory-based inquiry, seminar-driven knowledge construction, and self-directed learning modules. These elements collectively foster higher-order cognitive capabilities, design thinking, systems integration skills, and digital competencies, aligning curriculum delivery with the demands of Industry 4.0 and knowledge-driven economies. The framework is further supported by outcome-based teaching–learning and assessment mechanisms, integrating formative, diagnostic, and summative evaluation strategies within a credit-based flexible learning structure. Methodologically, the study employs a multi-phase iterative design, comprising policy analysis, stakeholder consultation, outcome mapping, pilot implementation, and qualitative validation. The framework is aligned with accreditation standards of the National Board of Accreditation and guidelines of the All India Council for Technical Education, ensuring both regulatory compliance and global comparability. Findings from the pilot implementation indicate that the proposed model enhances learner engagement, outcome attainment, interdisciplinary integration, and employability-oriented skill development, while demonstrating adaptability across institutional contexts. The study contributes a complexity-informed and scalable curriculum design model that bridges the persistent gap between policy intent and pedagogical practice. The case study of a 3D Printing course illustrates the operationalization of the framework at the micro-curricular level, including detailed outcome mapping, curriculum structuring, and assessment design. The proposed approach redefines curriculum design as a dynamic, feedback-driven, and competency-oriented system, offering a future-ready pathway for engineering education aligned with the transformative vision of NEP 2020.