For the better understanding we can use the analogy of VEHICLE DRIVING CAPABILITY
Board asks: What is accelerator, Clutch, Brake, Steering, Self-ignition & steps to use it in driving.
JEE Main / NEET asks: Ok drive forward, left, right, backward etc. & some times can ask the role of clutch and hydraulic braking systems.
JEE Advance asks: Let us take our vehicles, on the road, & driver through a stretch of ten kms., through traffic conditions, bad patches, & various turns. Those who reach first under reasonable time, know the driving well and the rest are rejected.
R E M E M B E R
The success in Board and Competitive exams is dependent on one basic parameter
"CLARITY OF FUNDAMENTALS"
So now you understand that competitive exams are just an extension of boards and it is possible to prepare both Board and Competitive Exams simulteneously, If one approaches in systematically planned and organized matter.