Diploma

Hello Sai,
This is the biggest example of bigoted thinking of politicians and all of us who elect them. Admissions in the 2nd year of engineering after completion the of Diploma is restricted to the students of that particular state only. I feel you should attempt to get admission in your own state.

Hi Nagendra,
For pursuing MBBS course, you need to appear for the NEET exam. The eligibility for NEET is as follows:
Educational Qualification
The aspiring candidates should have passed the 12th class examination, minimum of 50% (General category) and 40% (Reserved category) in the aggregate of Physics

Hello,
Yes, you can apply for JE (mechanical) in railways.
The JE exam is held for the junior engineers posts in different departments of the railways. You being ITI in Mechanical Engineering will get into mechanical department if you qualify in all the stages of the exam.
So, check the syllabus, grab

You are advised to appear in JEE Mains and JEE Advanced to seek admission in IITs after Diploma in engineering. IITs do not have lateral entry admission provision. DTU University conducts it's lateral entry admission test. Refer http://www.dtu.ac.in/Web/Admission/b.tech(LE).php.