This research aims to develop a multiscale modelling framework to predict fracture and fatigue behaviour in additively manufactured (AM) and repaired components. Addressing challenges such as microstructural heterogeneities, residual stresses, and defects, the model integrates crystal plasticity for micro-scale analysis and phase-field fracture methods for macro-scale failure predictions. By coupling fatigue indicators with adaptive numerical techniques, the framework captures crack initiation, propagation, and structural integrity under operational conditions. This approach provides a computationally efficient tool for optimising AM processes and repair strategies, ensuring safe and reliable applications in aerospace, automotive, energy, and space industries.