Hello,

I you don't fight for any competition exam like IIT JEE, comedk etc. you will get admission only on the basis of you 12th class marks. And in the current time almost all of the good engineering colleges give admission only on the basis of entrance exam marks. 

You can expect admission only in medium or low level private engineering colleges. I could be worth doing engineering from these colleges if the placement and faculty are average.

Thank you

Yes it is useful.

Don't get demotivated.

Not only iitians are successful. Many nitians bitsians bag top packages and work

Also many students from tier 3/4 colleges did get job in Google amazon Microsoft

It solely depends on your interest and dedication towards engineering.