You have fairly good opportunities after completion of your Diploma in Engineering. You have to decide yourself keeping your financial position and family needs in mind and choose one of the options before you- whether to go to job or continue your further studies. If you want to continue your studies, focus on the ICET examination conducted by the respective State Government where you would have a chance to join in the second year of the 4 year Engineering Graduation course i.e BE/B Tech based on the rank you get in the common entrance test. And you would be treated on par with the Engineering graduates after completion of the B Tech degree. You can appear for GATE examination and the score card would be helpful for seeking interviews in various PSUs and Government sector Engineering Trainee jobs. You can also try for on-campus/off-campus recruitment.
The other option – if you want to join a job after completion of your Diploma, you can. Just follow the advertisements in the News Papers/ Employment News. There would be more job avenues as a Technical Assistant/Junior Technical officer for Diploma holders in various organizations like NTPC, HAL, IOL, DRDO, BDL and other private sectors. Meanwhile you can also try for an internship in any of the well reputed organizations.