Certificate

So, what I have understood from your question is that, you have completed your Polytechnic and your result is awaited. If this is the case then you are eligible for giving JEE Mains examination, You will get provisional admission which will be confirmed once you get your 12th result.

I can understand your problem, but if you are able to check your mark sheet online, then you don't need to worry about the validation of the certificate. All the best for the bright future ahead.

No, it is not possible because you can take only a particular part of mechanical engineering.

Yes, it is enough, but do one thing. You can make a complaint letter to that board, you can get without mistake.

Hi Sayan Kundu,
It's a certificate course for full-time duration of 1 year.
The eligibility is that the candidate must have completed 10th from a recognized board and for admission, the interested candidate can apply directly to the college.
The basic course structure is as below:
1. Trade Theory
2. Workshop Calculation and Science
3. Trade Practical
4. Engineering Drawing
5. Employability Skills
For more details, click the link below:
https://www.shiksha.com/engineering/course/certificate-in-refrigeration-and-air-conditioning-srimati-techno-institute-hazra-kolkata-248218

You can try courses on Udemy or Coursera.

Hello,
The career options after completing professional certificate in photography are:
1. Photojournalist- where you can work for newspaper, magazines.
2. Scientific photographer
3. Forensic photographer
4. Feature photographer
5. Commercial photographers
6. Portrait or wedding photographer
7. Fashion photographer
8. Wildlife photography
9. Digital photography
You can work as a
Multimedia Specialist
Visual Merchandiser
Web Content Manager
Graphic Designer.

You can get various IT sector jobs after certification in CAD.