how can i get excellent calculas and conic sections, these two topics alkways trouble me in maths and i want to excel them,i always fail to learn the formulas and apply them in conic, right now i am referring tmh but some say sl loney is must, should i go for it a?

For calculas there is only solution i.e. practice.
Firstly, I would mention that before going to any advance book practice NCERT so as to clear all basics and all varieities of problem. Once you are done with it your formula problem will get solved.
Then for excelling you can go for advance books and practicing will make your calculas very good. My suggestion is any reputated book is good if you complete it but its good to practice versatile books for getting all variety of questions. For conics do parabola or any conic deeply then you will find same properties are there in every other conic. Make chart for studying conic where you will find general formulas for different conics are same and when you practice some questions you will feel comfortable with it.

For calculas tmh is good for conics you can go for SL Loney but definitely its not must. You can practice from any good book like tmh which you have right now. Make sure you do it completely and then go for other books.