The purpose of this study is to evaluate whether enhanced dermatologic management can reduce incidence of grade greater than or equal to (\>=) 2 dermatologic adverse events of interest (DAEIs) when compared with standard-of-care skin management and with modified enhanced dermatologic management in participants with locally advanced or metastatic stage IIIB/C-IV epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) treated first-line with amivantamab and lazertinib. The study also includes Expansion cohorts (in 2 different schedules) to evaluate enhanced dermatologic management and early intervention for DAEIs or paronychia, in participants receiving subcutaneous amivantamab and lazertinib. A substudy will enroll participants from Arms A and B who experience specific new-onset or persistent DAEIs (Grade \>=2) during treatment with intravenous (IV) amivantamab and lazertinib. This substudy aims to assess the reactive use of dermatologic treatment strategies in these participants.