I am 12th standard student aspiring to become an IAS officer, my stream is PCM with C++ , Could you please suggest me what courses should i

I am 12th standard student aspiring to become an IAS officer, my stream is PCM with C++ , Could you please suggest me what courses should i choose after 12th which can serve as a backup plan incase i am not able to clear IAS examination , i am a proficient in English,computer and chemistry