This question is unanswered so far, ITI and a lateral entry to a Diploma course or BE mechanical is being offered by many colleges.
1.Please check these details.
Is your degree Diploma in Mechanical Engineering given under the auspices of a recognised university?
Is it approved by UGC or AICTE?
2.You can visit AICTE website (https://www.aicte-india.org/opportunities/students/overview). It has a link (http://www.knowyourcollege-gov.in/) for you to know your college based on the state, district and the course type. you can verify the status of your degree and the college/university that has awarded it.
3.The Government of India has a National Apprenticeship Training scheme (NATS) (http://mhrdnats.gov.in/students). This website has four regions centres and four nodal centers with the address and contact details, you can contact them to see if you can imporve you skill set further and help you to gain employment (this is one of the main aims of this program). You can enroll and visit the students section or post a query (http://mhrdnats.gov.in/post-a-query) and try getting some guidance.
4.The government site of AICTE also has a list of placement links related to engineering jobs, take time to browse throught this. (https://www.aicte-india.org/opportunities/students/placements).
5.You have mentioned that you are from a poor family and looking for a job.
Have you registered in naukri.com
There are job adverts. for instance, one which needs diploma in mechanical engineering
6.There are jobs for freshers also
7.Please have a letter from the University/AICTE/UGC that your Diploma is recognised, then it will be easier for you for further work or studies. Please register in the above job portals and see to good openings that suits you.