Apart from parameters like the merit of students, the difference in fees, etc. But, in addition to that, there are quite a few differences between private engineering colleges and government engineering colleges.
However, not all who have passed from government colleges have made it big in life and more or less the same can be said about the students who have graduated from private universities. What matters is how you are making use of our college life. If you are passionate enough, you can get through any hurdle.
Government colleges also charge far fewer fees from the students than what private universities charge. So, there is financial freedom.