Hello, Himanshu 

Well , right we can't say anything about cut - off as it hasn't announced yet by NTA, since if you are gonna to give Jee mains in april then just revised from your class notes and solve previous year question this will be helpful, and to increase your score you should pay attention to important topic, like in maths , co-ordinate , calculas , in chemistry study full notes try to remember , for phyics it needs concept so you have to understand the concept of type of question ,sone important topic of phyics are optic, thermodynamics etc.

Work hard be positive all the best!!!!