JoSAA

You may get a seat in CSAB rounds but no chance in JoSAA rounds.

No, it is not necessary. Until you get a seat, no need to report. You also do not have to do anything other than to wait for further round cutoff.

It is not necessary, you can apply for IIIT as well as GFTI colleges also.

Yes, you will easily get ECE branch in a good IIIT at this rank through JoSAA counselling.

JEE Mains college predictor is an online tool which predicts the probable colleges based on the difficulty level of the examination, average marks scored in JEE Mains and seats available in IITs, NITs, GFTIs, and other SFTIs. The rank predicted might not be accurate but it certainly does give an idea to the aspirant. Know your college admission chances based on your JEE Mains rank, home state, caste, gender, etc., here:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor

Hi Harsha,
Yes, you will get the option for general EWS category at the time of filling the application form for the counselling. You should keep EWS certificate ready for verification at the time of counselling.
Best of luck.

NTA will officially declare it on its website. Documents required are nearly the same as every year. These documents are basically category certificate, class 12th certificate, birth certificate/class 10th passing certificate, medical certificate, Aadhar card/government valid ID, etc.

No, chance at this rank in JoSAA counseling.

Mostly only one language (English) would be considered and the other language would be neglected.

Yes, you can participate in JoSAA counselling, but I don't think you have any chance of getting a college.