A Phase 1/2, Multi-Center, Open-Label, Dose-Finding Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Preliminary Efficacy of BMS-986458, Alone and in Combination With Anti-lymphoma Agents in Participants With Relapsed/Refractory Non-Hodgkin Lymphomas (R/R NHL)

Inclusion Criteria: * Participants ≥ 18 years of age with R/R NHL (including DLBCL \[ie, DLBCL not otherwise specified (NOS) and diffuse large B-Cell lymphoma/high-grade B-Cell lymphoma with MYC and BCL2 rearrangements\], and FL): * For R/R DLBCL (de novo) and FL 3b: following at least 2 prior lines of therapy (eg, first-line combination chemotherapy regimen containing rituximab, anthracycline, an alkylating agent, and steroids and at least one additional treatment). * For R/R DLBCL (transformed lymphoma): following at least 2 prior lines of therapy which must have been administered after transformation. * For R/R FL (except for FL 3b): following at least 2 prior lines of therapy and meeting treatment criteria at the time of enrollment based on investigator´s assessment. * Participant must have measurable disease (defined by at least one FDG-avid lesion for FDG-avid disease and one bi-dimensionally measurable disease on cross sectional imaging by computed tomography or magnetic resonance imaging with at least one lesion \> 1.5 cm in the transverse diameter). * Participants must accept and follow pregnancy prevention plan. Exclusion Criteria: * Participants must not have an Eastern Cooperative Oncology Group (ECOG) performance status ≥ 2. * Participants with an inability to comply with listed restrictions, precautions and prohibited treatments. * Participants must not have prior CAR-T, or radiotherapy ≤ 4 weeks, systemic anticancer treatment ≤ 5 half-lives or 4 weeks, allogeneic SCT ≤ 6 months (only applicable to BMS-986458 single agent or rituximab combination cohorts), or autologous SCT ≤ 3 months prior to study intervention initiation. * In BMS-986458 + T-cell engager combination cohorts: Participants must not have prior alloSCT or solid organ transplantation, history of confirmed progressive multifocal leukoencephalopathy (PML); known or suspected history of hemophagocytic lymphohistiocytosis (HLH); known or suspected chronic active Epstein-Barr (EBV) infection. * Participants must not have any condition, including significant acute or chronic medical illness, active or uncontrolled infection, or the presence of laboratory abnormalities, that places participants at unacceptable risk if participating in this study. * Participants must not have known or suspected central nervous system involvement.