JEE Advanced

There is no state preference of state for admission in IITs. Do check the best option through Shiksha college predictor on
https://www.shiksha.com/college-predictor.

I think yes, but do check on the Shiksha college predictor.
https://www.shiksha.com/college-predictor

Under 4500 rank (not considering any branch) in JEE advance can give a seat in Bombay. For that, you need to more than 40% marks.

Don't think about the cutoff, if you belong to the general category try to get 33% marks at least 130+ to secure a seat in good iits.

Do type your rank on the Shiksha college predictor. https://www.shiksha.com/college-predictor.

Hello! Ishan, Yes you can get admission in IIST with your rank. This is a good rank.

Do check the college predictor of Shiksha to get more precise answer:https://www.shiksha.com/college-predictor

No you can't apply for EWS category in JEE advance.

For the year 2020 , 112 marks ( 28.28 % ) out of 396 was closing marks in general category. But this marks will vary from year to year depending on paper difficulty and the students who applied for IIST. In terms of rank , you can have target of getting rank under 10k as of now.
Hope it helps.

I would recommend you to make use of YouTube as well as some study material provided by some coaching institutes. You can borrow the study material from your relatives or some friend who have already passed his year.