became a teacher

If I understand your question right, Your question states that you are in 10th and a wondering what course to enroll your self into?

One should choose a stream after 10th that matches with your aptitudes and personality and keep options for future open.

Since I am not sure about your proficiency with computers and if your trying to build a carrier path go throw few suggestions listed below. Kindly pick the one that best suits you:

These are few trending computer courses. It can be learnt as part of academics or you can enroll for it later:

Cloud Computing, Parallel computing, Distributed Computing, virtualization, Networking, Programing, Designing, CCNA etc... The world of computers is very wide with ample choices.