Sikkim

Yes, if you can do computer Science in good manner and you have interest, you can take it's future is bright.

Please visit this link. This is a college predictor by Shiksha and I hope this will help you to choose the right college-
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor&ved=2ahUKEwie-7mvrITiAhWz73MBHYuID8oQFjAAegQIAxAB&usg=AOvVaw1N9BzFtyUCP4JU-2UQHQ0H.

The last year closing ranks at Manipal University Jaipur and MIT Manipal were 10867 and 1557 respectively. Hence, your chances are very good.

Hi,
Please visit Shiksha. Com's college predictor
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor. Ranks keeps on changing every year and differs from one branch to another and one college to another. If you fulfill the eligibility criteria of the specific institute you may complete further admission formalities. For now, I would suggest you to first contact the institute officials of the shortlisted universities directly for specific eligibility criteria details.

Admission Process:
Register and Apply - Interested candidates can apply online/offline with required information. Merit Screening - Admission is based on the marks obtained in graduation. https://www.shiksha.com/science/course/m-sc-in-geology-sikkim-university-gangtok-268581.

Hi,
Sikkim University offers M.Sc in Psychology, not industrial Psychology.

NIT Agartala is the Second Best after Silchar in NE states. Thus as per my view I would suggest you to go for SILCHAR -NIT is the best in terms of Placement
Infrastructure, Environment. Etc. Thus this purely on my views and as per this factor.

I would Suggest to go for NIT Silchar for mechanical or even Agartala is also better option among all as per my view as NIT - Agartala and NIT- Silchar have a good placement as per last 3year track record. And thus, the question for your answer is Silchar NIT is best for Mechanical as per view.

Yes, you can apply for NET exams.

Although, a candidate with a Bachelor's degree is eligible. But, distance degree is considered eligible or not, is not mentioned on the official website. I would rather advise you to get your doubts cleared by contacting the institute directly.