You fix your goal and find your path. You decide at an early age you want to be become a doctor. What kind not sure yet may be. So you are curious about science and learn as much as you can. You must score good enough in science, maths and English during your SSC. It will make you ready to work long hours, stay focused and learn new things without frowning and develop the ability to remember lot of things. It will help you develop your own brain. Then you must choose Biology as your subject in HSC and put your heart out to get good grades. At the same time you must try to understand what is that you are studying and while going through various aspects of biology it will help you think about how you want to contribute to the world. You must understand that being a doctor to earn lot of money is not the kind of world we want to live in. So you must inculcate feelings of compassion, analytical ability and if you happen to narrow down your thoughts to surgery, then you must learn to keep your mind serene. Once you get around 1000 Rank in your state, you have a good chance to get admission into good colleges. So you must look at the cut off of such colleges in the last 3-4 years and then plan your studies after your 11th vacation. Once you are done with your 12th exams, you must then think about which particular branch would suit you or what is the burning issue in the world around you that you want to be able to contribute or probably fix. So slowly following the journey you will reach there. You can talk to other doctors in various fields and learn about what they do in their every day life. You can talk to researchers. You can use platforms like LinkedIn or Quora to connect such professionals. Once you complete your graduation be it in medicine, dental, physiotherapy or any other field of your choice you may continue to become a master in that or continue with your service in hospitals, labs or research institutes.
By knowing where you want to go. By fixing what you want to become, you can follow the path to become that. Same way you can choose to become an engineer, banker, salesman, accountant, singer, painter, wildlife filmmaker, traveller, chef, journalist, model, astronaut, pilot, architect, designer, gamer, entrepreneur, businessman and so on.
Other ways to find your passion, niche and role in life is mentioned below :
You fix your vehicle and travel on your path
You fix your path and follow it to know where it leads
You keep hopping to the next best thing