Hello,

For you to be eligible for flying branch in IAF this is the eligibility criteria;

• You should be an Indian by nationality. You must either be appearing or have passed 12th with Physics and Mathematics to appear for NDA exam.
• For CDSE, NCC Special Entry and AFCAT candidates must be a graduate. Engineering degree holders can also apply for CDS Examination.
• Candidates must be below 25 years and should be unmarried.
• Married candidates above 25 years can apply, but during the training period they will not be provided separate accommodation for the spouse .

Flying Branch through AFCAT and NCC Special Entry:

• You should be between 20 and 24 years as of January 1, 2022.
• You must have born between January 2, 1998, and January 1, 2002.
• The upper age limit of candidates having a valid and current commercial pilot license issued by DGCA is relaxed upto 26 years.

You see maths is really important for flying branch so you cannot apply with PCB.

https://afcat.cdac.in/AFCAT/CareerAsPerBranches.html

You can check all the details here.

Hope this helps!!