If you want admission in B. Tech./B. Sc. programs, you need to give JEE and have to score really good in it to get into IITB-CSE.

If you want to go for M. Tech or MSc you need to give GATE or JAM respt., again need to score damn well to get into IITB.

You can see the last year's stats for some idea.

As for fee, given you perform decent and your father's income is below a limit, you can get MCM scholarship in which tuition fee is waived, which is 60% of it. Still, you'll be paying 25 K per semester, if it has not increased much more.

If you're going for M. Tech., which I think you are, you can easily become a TA and earn 10-12K a month. It'll help you in your academics as well.

They also have the facility of loan sanctioned from the Dean, with a interest rate of about 4%, quite low than the market. Maybe they've discontinued it but I don't think so.

Feel free to ask me in the comment box if you are having any further doubts

hope you find it helpful

Good Luck!