Inclusion Criteria:

          -  Phase 1 and Phase 1b lazertinib+Amivantamab combination cohorts: Histologically or
             cytologically confirmed non-small cell lung cancer (NSCLC) with previously epidermal
             growth factor receptor (EGFR) mutation (identified locally in a Clinical Laboratory
             Improvement Amendments [CLIA]-certified laboratory [or equivalent]) that is metastatic
             or unresectable, and have progressed after standard of care front-line therapy, and
             exhausted available options with targeted therapy. A participant who has refused all
             other currently available therapeutic options is allowed to enroll

          -  For the Phase 1b Lazertinib, Amivantamab and Platinum-doublet Chemotherapy (LACP)
             combination cohort: histologically or cytologically confirmed advanced or metastatic
             EGFR-mutated NSCLC who have progressed on or after an EGFR-TKI as the most recent line
             of treatment with a maximum of 3 prior lines of therapy in the metastatic setting
             allowed

          -  For all expansion cohorts, the EGFR mutation must have been previously histologically
             or cytologically characterized, as performed by a CLIA-certified (US sites) or an
             accredited (outside of US) local laboratory, with a copy of the mutation analysis
             being submitted during screening (Phase 1b expansion Cohort B, C and D)

               1. Expansion Cohort A: Participant must have advanced or metastatic EGFR-mutated
                  non-small cell lung cancer (NSCLC) that has progressed on prior treatment with
                  osimertinib in the first or second line, followed by progression on a
                  platinum-based chemotherapy regimen as the last line of therapy prior to study
                  enrollment. Prior use of first or second generation EGFR tyrosine kinase
                  inhibitor (TKI) is allowed if administered prior to osimertinib

               2. Expansion Cohort B: Participant must have previously treated, advanced or
                  metastatic NSCLC with documented primary EGFR Exon 20ins activating mutation.
                  Participants should have been treated with standard of care, platinum-based
                  chemotherapy regimens, but may have treated with approved EGFR TKI,
                  investigational EGFR, or immunotherapy agents if refusing front line
                  platinum-based chemotherapy standard of care. Up to 3 lines of prior systemic
                  anti-cancer treatment are allowed

               3. Expansion Cohort C: Participant must have advanced or metastatic NSCLC
                  characterized by an uncommon activating mutation Additional uncommon EGFR
                  mutations/alterations, beyond those listed above, may be considered for
                  enrollment after agreement with the medical monitor. Participants may be
                  treatment naïve or have been treated with one prior line of therapy which must be
                  a first or second generation TKI (that is gefitinib, erlotinib, afatinib) in the
                  most recent line of therapy. Prior chemotherapy is allowed if administered prior
                  to EGFR TKI therapy, or as the only systemic anti-cancer therapy prior to study
                  enrollment. Up to 2 lines of prior systemic anti-cancer treatment are allowed

               4. Expansion Cohort D: Participant must have advanced or metastatic EGFR-mutated
                  NSCLC (EGFR Exon19 deletion or L858R) that has progressed on prior treatment with
                  osimertinib in the first or second line (after first- or second-generation EGFR
                  TKI), as the immediate prior line of therapy. Only previous treatment in the
                  metastatic setting with a first, second, or third generation EGFR TKI is allowed

          -  Evaluable disease

          -  Eastern Cooperative Oncology Group (ECOG) performance status grade of 0 or 1

          -  Participants must meet the study protocol defined laboratory criteria without having a
             history of red blood cell transfusion, platelet transfusion, or granulocyte-colony
             stimulating factor support within 7 days prior to the date of the test

          -  A woman of childbearing potential: Must have a negative serum beta human chorionic
             gonadotropin at screening; Must agree not to breast-feed during the study and for 6
             months after the last dose of study intervention. (Enrollment is not allowed even if a
             woman who is breast-feeding stops breast-feeding); Must agree not to donate eggs (ova,
             oocytes) for the purposes of assisted reproduction during the study and for 6 months
             after receiving the last dose of study intervention

        Exclusion Criteria:

          -  Participant has an uncontrolled illness, including but not limited uncontrolled
             diabetes, ongoing or active infection (includes infection requiring treatment with
             antimicrobial therapy [participants will be required to complete antibiotics week
             prior to study treatment] or diagnosed or suspected viral infection); active bleeding
             diathesis; Impaired oxygenation requiring continuous oxygen supplementation;
             Refractory nausea and vomiting, chronic gastrointestinal diseases, inability to
             swallow the formulated product, or previous significant bowel resection that would
             preclude adequate absorption of study treatment; or psychiatric illness or any other
             circumstances including (social circumstances) that would limit compliance with study
             requirements. Any ophthalmologic condition that is either clinically unstable or
             requires treatment

          -  Prior treatment with antiPD-1 or anti Programmed death-ligand 1 (PD-L1) antibody
             within 6 weeks of planned first dose of study intervention

          -  Untreated brain or other central nervous system (CNS) metastases whether symptomatic
             or asymptomatic. Participants who have completed definitive therapy, are not on
             steroids, and have a stable clinical status for at least 2 weeks prior to study
             treatment may be eligible for Phase 1b expansion cohorts. If brain metastases are
             diagnosed on Screening imaging, the participant may be enrolled, or rescreened for
             eligibility, after definitive treatment if above criteria are met

          -  Any Toxicities from prior anticancer therapy must have resolved to common terminology
             criteria for adverse events (CTCAE) version 5.0 Grade 1 or baseline level (except for
             alopecia [any grade], Grade <=2 peripheral neuropathy, and Grade <=2 hypothyroidism
             stable on hormone replacement therapy)

          -  Allergies, hypersensitivity, or intolerance to Lazertinib or JNJ-61186372 or their
             excipients. For the LACP combination cohort: participant has a contraindication for
             the use of carboplatin or pemetrexed (refer to local prescribing information for each
             agent). Participant has a history of hypersensitivity to, or cannot take, vitamin B12
             or folic acid