Just work on your Mathematics, be strong and start loving Programming, whatever is taught at school level. Start practicing Programming questions on your own, may even start doing preliminary Programming Questions from Higher Classes (9,10,11,12). Try to develop your intellect, solve a lot of Aptitude Questions, IIT Foundation Mathematics as well as Try to start interpreting Data from Charts, etc. Get versed with Microsoft Office Applications like Excel. This would be enough for foundations.

Once in your Class 11 and 12, you may start Python as well as Studying Statistics seriously. May start loving Python as do it as a hobby, practice Questions, Data Analysis during your Vacations, besides focussing on your 10+2 Exams and Entrance Tests.

Apart from that, once in College, you may finally strt with Data Science and ML, do Projects and Internships, and definitely start of a career in Data Science in future.