Hey pratibha,

hope you are doing great, first of all congratulations you started thinking so early regarding preparation hope it will give another edge in competition. First of all you have to decide in which subject you need to give your jam exams generally in one subject around 15000 students appear in any paper of the JAM. you should follow some of the books which can be helpful. Following are some books which you can refer https://www.amazon.in/-/hi/dp/B0772PC965

give mocks regularly stay motivated.

All the best!