Shri G. S. Institute of Technology and Science

You are too close to it. Last year, IP was closed at 141. This year, as the cutoff has fallen down a lot, you might be getting IP or civil easily, try for mechanical or chemical, but don't stretch for CSE and IT as you won't be able to get it through home state quota too.
Best of luck.

Yes, you have a good ST rank and accompanied with HOME - STATE quota, you'll easily get one out of four branches in
Be your priority with CSE then IT, ECE, EEE and MEC. Mechanical is more wider branch now a days and frankly many options and you don't need a high study load. Still, if you can study and dedicate more hours, then opt for CSE.
Best of luck.

With OBC, 91 marks, You'll get mechanical or civil in second or third round. Moreover, I would suggest you to push till third round. Also, if you wish to get even better, be a part of spot round, though that might be a bit risky and be a part of that if you secure a seat through josaa first.
Best of luck.

Kindly refer to my answer below:
https://ask.shiksha.com/can-i-get-ec-branch-in-sgsits-with-16964-obc-rank-and-63k-air-qna-4833495

Talking about marks, last year:
IP - 148 ( general Home state )
CSE ( 188 )
IT ( 184)
MECHANICAL ( 160 )
CIVIL ( 155 )
ECE - 178
EEE - 170
Best of luck.

You need to give JEE Mains and qualify it. At least for admissions in HOME -STATE and general, you need around 148 marks in Industrial and production. Moreover, you need at least 190 marks for getting a top notch as CSE. Through JOSAA, apply through the online portal the dates for the first round is from 15th June and 25th June.
Best of luck.

Assuming you are from General category, getting into CS is tough for you as for out state students, last year's cutoff was 180 and that too for home state. I would suggest you to get a college in Jaipur or Udaipur with home state as most of the seats in sits are filled by home state itself. Else, try for private colleges with better placements.

You need all the documents required by NIT for admissions. Do not worry about everything else. For NIT, You need your 12th marksheet and school-leaving certificate. Admissions have been started from 15th June itself and the first round will go up to 25th June.
Best of luck.

SGSITS is good for placements. Being an autonomous institute, the companies prefer it over, private colleges of the region, The highest package one recruited was Microsoft through campus placements of around 24 Lacs per annum. Moreover, if you are in one of the core branches of GSITS, you'll get recruited as the number of students are not more than a certain number and every year, there are around 95% placements. Best of luck.

Depends on which branch you are getting transferred. If you are doing it from CSE just for the sake of a good college, I'll not suggest it. Frankly, Industrial and Production engineering is something can be easily learnt and done after the graduation. It comes more from experience and exposure rather than Degree. Also, in GSITS, IP does not have a big name, so I'll not suggest it.
Best of luck.