There is no requirement to have Physics, Chemistry, and Math (PCM) in 12th to appear for JEE Mains 2025. You must have passed the class 12 exam in 2023, 2024, or 2025 .You need to have studied at least five subjects in your qualifying exam, with Physics, Chemistry, and Mathematics being mandatory. This means your PCB combination fulfills the Physics and Chemistry requirement.

Since you haven't studied Math in 12th, you need to put in extra effort to build a strong foundation in Mathematics, which is a crucial subject for JEE Mains.Qualifying for JEE Advanced, which allows admission to IITs, requires Mathematics at the 12th-grade level.

https://engineering.careers360.com/download/ebooks/jee-main-2022-preparation-tips

I hope it helps!