Company Secretary

Both are professional courses. You can do whatever interests you the most.

There is acute shortage of good experienced computer science graduates abroad particularly in USA, UK and EU. This shortage is fulfilled by IT companies by providing experienced CS resources on staff augmentation mode from India. Good experienced Indian, CS professionals are able to get good jobs abroad. However, there are visa restriction challenges, which may damp your plan for job abroad.

Yes, you can. After completion of CS foundation, one may register with ICAI-IPCC and get enroll as IPCC student either with first group or both groups.

Yes, you can do CS from any good institute via regular mode.

Your question is not clear. You are requested to reframe your question for an appropriate and right advice.

If you are good in theoretical subjects, you should go for CS.
In CA, you will learn major portion of accountancy.
In CS, you will learn many laws & regulations related to company.
Best of luck for your future.