Colleges in Delhi

Yes friend, you can get SRCC, Delhi University with these marks. It may be 1st or 2nd round of cutoff list.

No, you can't do that after final submission of your application. You should contact DU helpline.

Generally, it depends on the subject/ course you choose and your category. But with these marks I think you can get seat in 1-3rd round.

Hello, with this rank in JEE main you won't get a seat in any government colleges for engineering for sure. Actually all the seats get exhausted at around 50k, so please go for best private engineering colleges like Sharda, Amity etc. Please visit this link for more such colleges
https://www.shiksha.com/b-tech/ranking/top-engineering-colleges-in-delhi-ncr/44-2-0-10223-0

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