Along with the inherent remarkable properties of graphene, adatom-intercalated graphene-related systems are expected to exhibit tunable electronic properties. The metal-based atoms could facilitate multi-orbital hybridizations with the out-of-plane π-bondings on the carbon honeycomb lattice, which dominate the fundamental properties of chemisorption systems. In this work, using first-principles calculations, the feature-rich properties of alkali-metal intercalated graphene nanoribbons (GNRs) are investigated, including edge passivation, stacking configurations, intercalation sites, stability, charge density distribution, magnetic configuration, and electronic properties. There exists a transformation from finite gap semiconducting to metallic behaviors, indicating enhanced electrical conductivity. It arises from the cooperative or competitive relations among the significant chemical bonds, finite-size quantum confinement, edge structure, and stacking order. Moreover, the decoration of edge structures with hydrogen and oxygen atoms is considered to provide more information about the stability and magnetization due to the ribbons' effect. These findings will be helpful for experimental fabrication and measurements for further investigation of GNR-based materials.