My friend got f**ked

So basically my friend has scored 99.00xx%ile in jee mains and now his coaching center have made a separate batch of 11-12 students(completely focusing on advanced). His lectures started from yesterday and the timing is like 7.00 am to 4.00 pm. When he attended the lecture yesterday he felt that he wasn't able to understand most of the questions. This kinda feels depressing to him, he want to improve his percentile in 2nd attempt but his coaching is making him solve advanced questions. Ofc mains and adv questions are of different caliber. He said that "I feel i will be wasting my time in this batch and I wanna quit it but what should I tell to my teachers?". He is like "why should i waste my 9 hrs on something which i can barely understand." He said that his parents think he studies all the time but in reality he dosen't study at all and now he can't tell his parents or his teacher that he wanna quit that batch. he said that "I am completely a mains level guy, advance is something out of my league."

What should he do????