Inclusion Criteria for All Participants:  ECOG performance status of 0 or 1  Inclusion Criteria for Participants with Early-stage NSCLC:  Participants must have a complete resection of a histologically or cytologically confirmed Stage IIB-IIIB (T3-N2) NSCLC PD-L1 expression TC ≥ 1% or TPS ≥ 1% Participants must have completed adjuvant chemotherapy at least 4 weeks and up to 12 weeks prior to randomization and must be adequately recovered from chemotherapy therapy  Inclusion Criteria for Participants with Stage IV NSCLC:  Histologically or cytologically confirmed, Stage IV non-squamous or squamous NSCLC Life expectancy ≥ 18 weeks PD-L1 expression TC ≥ 50% or TPS ≥ 50% or TC3 or IC3 No prior systemic treatment for Stage IV non-squamous or squamous NSCLC Participants who have received prior neo-adjuvant, adjuvant chemotherapy, radiotherapy, or chemoradiotherapy with curative intent for non-metastatic disease must have experienced a treatment-free interval of at least 6 months from randomization since the last chemotherapy, radiotherapy, or chemoradiotherapy cycle.  Exclusion Criteria for All Participants:  History of malignancy within 5 years prior to initiation of study treatment, with the exception of the cancer under investigation in this study and malignancies with a negligible risk of metastasis or death Uncontrolled tumor-related pain Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures Participants known to have a sensitizing mutation in the EGFR gene or an ALK fusion oncogene History of leptomeningeal disease Uncontrolled or symptomatic hypercalcemia Active or history of autoimmune disease or immune deficiency History of idiopathic pulmonary fibrosis, organizing pneumonia), drug-induced pneumonitis, or idiopathic pneumonitis, or evidence of active pneumonitis on screening chest computed tomography (CT) scan Significant cardiovascular disease within 3 months prior to initiation of study treatment, unstable arrhythmia, or unstable angina  Exclusion Criteria for Participants with Stage IV NSCLC:  Symptomatic, untreated, or actively progressing central nervous system (CNS) metastases