Sir I am at this time in class 10 so I want to crack IIT and join collage but what I do please help me
First of all congratulate yourself because you have dare to dream big. Most of people think cheap so they get cheap.
It's not much earlier too start. So, first just give full focus on basics. I will not recommend you to buy any JEE preparation books. Give more study hours to maths and science. Go as much as you can go in concepts.
So, you are in 10th and using smartphone too. So don't waste your time in bullshit like Instagram, Facebook etc. Subscribe some educational channels on YouTube. Install some quiz games. Buy some magazines about science and maths.
In free times you can chill with friends.!! Yes, you can but just don't make it habbit. You are in 10th buddy. In Golden days of life so don't forget to enjoy as much as you can in schools.
Just only thing in making good memories with friends don't forget about your goal. This is all you have and this is what you will make successfull in upcoming years.
Just work hard, so when you get your result you don't say I regret it but you say it was worth it.