Inclusion Criteria - Participants must have histologically confirmed Stage IV or recurrent Non-small Cell Lung Cancer (NSCLC) of non-squamous (NSQ) histology with tumor cell PD-L1 expression 1% to 49% as determined by a central laboratory - Participants must have measurable disease by computed tomography (CT) or magnetic resonance imaging (MRI) per RECIST v1.1 criteria. - Participants must have an Easter Cooperative Oncology Group (ECOG) performance status of ≤ 1 at screening. - Participants must have no prior systemic anti-cancer treatment given as primary therapy for advanced or metastatic disease. Exclusion Criteria - Participants must not have epidermal growth factor receptor (EGFR) mutations, anaplastic lymphoma kinase (ALK) translocations, ROS-1 translocations and known BRAFV600E, that are sensitive to available targeted inhibitor therapy; participants with known activating rearranged during transfection (RET) mutations and neurotrophic tyrosine receptor kinase (NTRK) fusion gene alterations. - Participants must not have untreated central nervous system (CNS) metastases. - Participants must not have concurrent malignancy requiring treatment or history of prior malignancy active within 2 years prior to randomization. - Participants must not have an active autoimmune disease. - Participants must not have history of interstitial lung disease or pneumonitis that required oral or intravenous (IV) glucocorticoids. - Participants must not have a history of myocarditis, regardless of etiology. - Participants must not have had prior treatment with an anti-PD-1, anti-PD-L1, anti-PD-L2, or anti-CTLA-4 antibody, or other antibody or drug targeting T-cell co-stimulation or checkpoint pathways. - Other protocol-defined Inclusion/Exclusion criteria apply.