To become an IAS officer, one has to clear UPSC examinations. There are a lot of articles and resources available online to guide you through the structure of UPSC examinations. You can get yourself registered in an institution to have a more structured and aggressive schedule.
A few habits that will help one to clear these exams - Reading newspapers, Having an opinion or a view on various topics you come across, debating about various issues. These things will help you have a mindset that is required for the job.
NCERT textbooks (1st - 12th Standard).
Ruchi recommends the following next steps: