Certificate

You can use Shiksha college predictor
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor
Good luck.

You are not qualified to get a college but you can apply for the counseling.

Yes, any person can but for that, you need to write an application and submit it to them just to have a proof of you have collected the document. In some cases, they may ask a reason for it and can ask that person for a yes on call.

This would depend a lot on which specific area in finance would you be keen on perusing a career in. In case you are keen in Equity markets then there are a host of certifications/Diploma courses that are run by BSE /NSE you could explore them. If you want to pursue a career in Accounts then you could look at gaining expertise in some of the accounting software that are used in organisations, you could also pursue short term course in Taxation /corporate law.

I am unable to understand your question, can you please type again so that I can help you out?

Yes, the EWS certificate is required at the time of registration for DU.