Query regarding CLAT and JGLS and strategy.....

My brother has just started preparing for CLAT 2027, this month(literally 2 days ago). He scored just 45 in his first mock. He took a drop(due to health issues) who started late although he did score 91 percent in boards. If we downloaded 20 mocks from Legal edge, cleared all concepts, wrote those questions multiple times, we would be doing around 2000 questions. Would that suffice for a decent 80-85 plus score? If not, if he prepares for LNAT---JGLS post December 6th for a month.....what are his chances of getting success? Bare with me, I'm not a law background guy and don't know much about CLAT.