Hello there!

Greetings!

To prepare conic sections for jee mains first of all go through the chapter from ncert , it will clear your basic concepts, but when it comes to jee then doing  conic section from  ncert is not enough so after completing it from ncert you should then go through the chapter from RD sharma and then practice past year questions of jee from conic sections. You can also follow book by cengage. There a number of formulas in this chapter,  you should make a list of the formulas and you should keep revising them from time to time.
Good luck for your jee preparation

Thankyou