Commerce

You need to complete your post-graduation first and then go for B.Ed. degree.

If you are interested, then yes. Hotel management has a great scope in India as well as abroad.

Diploma after 11th wont help you much professionally. I would suggest you to complete your 12th first and then apply for B.Arch through JEE or NATA.

You will have to appear for the entrance exam conducted by NIFT and if you happen to get good marks then surely you can get admission in NIFT.

You can change your stream in class 12th itself but it will be difficult to study different subjects. Consult your school teachers, they can guide you better than online forums.

You should opt for B.Com or BBA, and then pursue MBA in entrepreneurship.

You may find it difficult to study in the field of automotive because of your lack of PCM background. It is unfair but it is the reality of our education system.

If you take Commerce plus IP with Maths, you will be eligible for do B.Com, BCA, BBA, law, Hotel management. CA, CS, etc. at graduation level. You will be eligible for all Government Class I and subordinate services jobs after graduation degree in your chosen field.

In commerce stream, there are lot of space to make career in various courses like:
(1)B.com : For being proffecer,CA,PA and many other
(2)LLB. - For lawyer
(3)BSW. - For social worker
(4)BCA. - For computer application
(5)B.sc IT. - For information technology
(6)BHRD
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Best of luck.

Diploma is the course which you can do after your 10th. After 12th from commerce, you can do B.Com, BBA, BA, etc.