Diploma

Hi Piyush,
Let me tell you that the basic eligibility criteria for BE / B.Tech in Automobile Engineering is 10+2 or equivalent examination with Physics, Chemistry and Mathematics or Bio-technology, bioinformatics, Biomedical with a fairly high percentage of marks in the aggregate.
However, After 10th

You have to sit for various entrance exams and look for colleges which provide particularly automobile engineering or you can go for mechanical engineering and later get you a higher degree in automobile engineering.

Please refer to the link provided below where you can download college brochure which contains important details regarding fee structure for Diploma in Hotel Management and Catering Science from The National Institute of Hotel Management.
https://www.shiksha.com/hospitality-travel/hotel-hospitality-m

Hi, Please find the list of colleges below:
1. Indian Institute of Technology, Madras
2. Indian Institute of Technology, Bombay
3. Indian Institute of Technology, Kanpur
4. National Institute of Technology, Rourkela
5. Vellore Institute of Technology
6. National Institute of Technology, Surathkal.

After getting result you need to feel cap round form online for colleges if you are selected for cap round then you can take admission for Diploma in Computer Engineering in VJTI Mumbai.

Diploma courses after 10th:
Diploma in Mechanical Engineering
Diploma in Computer Engineering
Diploma in Electrical Engineering
Diploma in Electronics and Telecommunication Engineering Diploma in Information Technology Engineering
Diploma in Chemical Engineering.

Yes, it is applicabe for diploma student you just have to agree to their terms and conditions and clear their entrance exam then you will be applicable for that.
Best of luck for your future.

I don't think you'll get admission in RGIT. If you belong to some category other than OBC and open, then maybe you've some chance of getting admission in second or third round.