Commerce

Hello,
Your query is a little difficult to understand. One does not require polytechnic to complete 12th. In fact after 10th you can go to a polytechnic to pursue skill based training. You have to go to a normal college for doing 12th.

You have many options in commerce like B.Com, BBA, BBM, CS, CA, CMA, LLB and B.Lib.

If you are already a commerce graduate then there is no point on doing B.Com corporate secretaryship. For those pursuing a CS course there is no special job available for those doing corporate secretaryship. Yes, from knowledge gaining point of view, you may think about it.

You can go for following options:
B.Com MBA
B.Com MCA
BBA MBA
BBM MBA
B.Com LLB
BA LLB
Advertising
Hotel management

The main difference between CA CS studies is that in CS, you are going to learn more about company law and in CA, you are going to learn more about accounting and taxation.

You have many options like:
B.Com
BBA
BCA
BBM
BA
Hotel management
Mass communicationAdvertisingAnimation
LLB
You also have options like:
CA CS CMA with B.Com
Short term diploma like
Diploma in taxation
Diploma in foreign trade
Diploma in import and export
Other than this you can learn foreign language like French.

If they are not giving you the certificate you must request them for that.

You may refer to India Today 2016 ranking of India's top commerce institutes: http://indiatoday.intoday.in/bestcolleges/2016/ranks.jsp?ST=Commerce&Y=2016

After 12th, you have options of doing BCS and side by side, start learning computer language like java, c+, etc.

If you want to do CA then apply for CPT and clear your CPT and while doing CA, you can do B.Com form any college. If you are doing external .Com, it will help you for doing CA.